ChatGPT answers, unedited

If your goal is retargeting existing mobile-app users across both the open web/in-app inventory and social, I’d separate the problem into two layers: media buying and measurement/audience orchestration.

My shortlist

If I were building the stack

For a performance app marketer, I'd start with:

Moloco + Meta + TikTok + an MMP such as AppsFlyer/Adjust/Branch/Singular.

Moloco is particularly interesting because its re-engagement product is explicitly designed to reactivate existing/lapsed app users, and it says its inventory reaches 2.8M independent apps. Moloco Moloco It also requires MMP integration so it can receive post-install events and optimize toward them. Moloco Ads Help Center

For open-web/in-app programmatic, Liftoff is another strong choice. Its Accelerate product explicitly supports user re-engagement, while its broader DSP infrastructure gives access to programmatic inventory. Liftoff Liftoff

The important caveat is that no single platform is ideal for "open web + every social platform." Meta and TikTok largely require their own buying environments, while DSPs such as Moloco/Liftoff/TTD handle programmatic inventory. So I'd avoid choosing a single vendor based on the premise that it can efficiently cover everything.

One architecture I'd recommend

MMP / CDP
→ build audiences such as:

• Installed but never purchased
• Purchased 30–90 days ago
• Abandoned checkout
• High-LTV users becoming inactive
• Lapsed users
• Exclude users who converted recently

Then activate those audiences through:

• Moloco or Liftoff → programmatic in-app/open-web re-engagement
• Meta Ads → Facebook/Instagram
• TikTok Ads → TikTok
• Google DV360 → if you need significant broader web/display/video/CTV reach

Your MMP should remain the source of truth for conversion and incrementality, rather than letting each ad platform define success independently. AppLovin, for example, currently lists Adjust, AppsFlyer, Kochava, Tenjin, Singular and Branch as supported third-party tracking vendors. AppLovin | Support Center

My ranking

If you told me "I have a $100k+/month app retargeting budget and want the best performance," I'd test:

1. Moloco — first choice for mobile-app re-engagement
2. Meta — essential social channel
3. TikTok — depending on audience/creative fit
4. Liftoff — strong second DSP to test against Moloco
5. DV360 / The Trade Desk — add when you need substantially broader web/video/CTV reach

One particularly interesting option is Liftoff's App-to-Web capability if your objective is actually to take people who have used your app and drive them to a mobile website conversion rather than back into the app. Liftoff explicitly positions that product around targeting in-app users and optimizing for mobile-web conversions. Liftoff

If you tell me your app category, monthly retargeting spend, iOS vs. Android split, and whether the desired conversion is purchase/subscription/return-to-app, I can narrow this down to a specific stack and explain which vendor I'd put the first $50k into and why.

One architecture I'd recommend

MMP / CDP
→ build audiences such as:

If your goal is retargeting people who already use your mobile app across both the open web and social, I’d shortlist these:

My recommendation

For one platform spanning open-web + social, start with Criteo. Its app-retargeting product can reach existing app users across mobile websites and in-app environments, while its broader retargeting offering covers open web, social, video, and in-app inventory. help.criteo.com

Criteo Mobile App Advertising

If you're primarily a mobile app performance marketer rather than an e-commerce advertiser, I'd also evaluate Moloco and Remerge. Moloco explicitly supports re-engagement campaigns optimized for clicks, opens, in-app events, and ROAS. help.moloco.com Remerge is particularly focused on mobile app retargeting and has extensive in-app supply. www.remerge.io

Moloco Ads

Remerge

Don't try to make one tool do everything

A strong stack would be:

MMP → DSP for open web/in-app → Meta + TikTok for social

For example:

AppsFlyer/Adjust/Branch → Criteo or Moloco → Meta + TikTok

This gives you much better control over audience segments such as:

• installed but never purchased
• viewed product but didn't purchase
• cart abandoners
• purchasers eligible for cross-sell
• dormant users
• high-value users
• users who uninstalled

TikTok supports app retargeting through MMP integrations including AppsFlyer, Adjust, Branch, Singular and Kochava. ads.tiktok.com Its current App Promotion product explicitly supports re-engaging existing app users, including optimization toward in-app conversions. help.moloco.comwww.remerge.ioads.us.tiktok.com

If you tell me your app category (e-commerce, fintech, gaming, subscription, delivery, etc.), monthly ad spend, and whether you're on iOS/Android/both, I can narrow this to the 2–3 platforms I'd actually test and explain the likely economics.

If your goal is retargeting existing mobile-app users across both the open web and social, I’d use a mobile measurement/audience platform + multiple media buying channels, rather than trying to make one ad platform do everything.

My shortlist

\*Meta/TikTok have their own broader ad ecosystems, but they're not substitutes for an independent open-web DSP.

Why I particularly like AppsFlyer for this use case: you can create audiences based on actual app behavior—e.g. installed but never purchased, purchased 30+ days ago, high-LTV users, churn-risk users—and synchronize those segments to Meta, Google, TikTok and 140+ partners, including programmatic DSPs. www.appsflyer.com

It also handles the attribution/deep-linking side of retargeting, including distinguishing re-engagement from re-attribution after reinstall. support.appsflyer.com

The stack I'd actually build

App → AppsFlyer/Adjust → audience segments →

• Meta → Facebook + Instagram
• TikTok → TikTok
• Google Ads → Google Display/YouTube
• DSP → open web/programmatic inventory

For example:

User opens app → views product → doesn't purchase → enters "product viewers/no purchase" segment → AppsFlyer syncs audience → user sees Meta ad + TikTok ad + programmatic web ad → click opens the relevant screen in the app via deep link.

Google supports app remarketing audiences and can send users with the app installed directly back into the relevant app experience; users without the app can be directed to the website. support.google.com

TikTok likewise supports app retargeting based on in-app events and works with MMPs including AppsFlyer, Adjust, Branch, Singular and Kochava. ads.tiktok.com

If you want the simplest answer

I'd start with AppsFlyer + Meta + Google + TikTok. Add a DSP such as The Trade Desk when you need meaningful open-web/programmatic scale beyond Google's inventory.

If you tell me your monthly retargeting budget, app category, iOS/Android split, and whether you need web + mobile-web + in-app inventory, I can narrow this down to a specific stack and estimated costs.

If your goal is retargeting existing mobile-app users across both the open web and social, I’d use a combination of an MMP/audience layer + specialized media buyers, rather than trying to find one tool that does everything.

My shortlist

What I'd actually build

1. AppsFlyer as the measurement/audience layer.
You can build segments based on installs, in-app events, LTV, churn risk, etc., then automatically sync them to Meta, Google, TikTok and 140+ partners. AppsFlyer also supports retargeting attribution and deep linking. www.appsflyer.com

2. Liftoff or Criteo for open-web/programmatic retargeting.

• Liftoff is particularly compelling if you're a mobile-first app business. Its re-engagement product is specifically designed to bring dormant app users back, using ML optimization and programmatic inventory. liftoff.ai
• Criteo is particularly strong for commerce. Its app retargeting reaches users across mobile web and in-app environments and can deep-link them back into the app. help.criteo.com

3. Run native social retargeting separately.
For Meta, TikTok, etc., I'd generally use their native buying platforms rather than trying to force social inventory through a DSP. AppsFlyer can feed your audiences into those networks. TikTok, for example, explicitly supports app retargeting through MMPs including AppsFlyer, Adjust, Branch, Singular and Kochava. ads.tiktok.com

If I had to pick one setup

Most mobile-app companies:
AppsFlyer + Liftoff + Meta + TikTok

E-commerce app:
AppsFlyer + Criteo + Meta + TikTok + Google

Large advertiser with sophisticated programmatic buying:
AppsFlyer + DV360 + Meta + TikTok, potentially adding Liftoff/Criteo for incremental app-retargeting inventory.

One important caveat: “retargeting across the open web and social” isn't as deterministic as it used to be, particularly on iOS. Device identifiers and other signals are increasingly restricted, so you should evaluate vendors on their privacy-preserving measurement, audience matching, deep linking, and incrementality capabilities—not just their claimed reach. support.appsflyer.com

If you tell me your app category (e.g. gaming, fintech, e-commerce, subscription), monthly active users, geography, and approximate monthly retargeting budget, I can narrow this down to the 2–3 platforms I'd shortlist and how I'd split the budget between them.

If your goal is one retargeting stack that can reach existing mobile-app users across both the open web and social, I’d shortlist these:

My recommendation

For most app marketers: use AppsFlyer as the audience/measurement layer, then combine a programmatic DSP with the major social networks.

AppsFlyer can build behavioral segments from installs, in-app events, LTV and churn signals and sync them to Meta, Google, TikTok and 140+ partners. www.appsflyer.com It also supports retargeting attribution for both re-engagement and re-attribution/reinstall campaigns. support.appsflyer.com

A practical stack would be:

AppsFlyer → Liftoff or Moloco → Meta + TikTok + Google

That gives you:

• Open web: DSP inventory
• In-app inventory: mobile-app exchanges
• Facebook/Instagram: Meta
• TikTok: TikTok
• YouTube/display: Google
• Audience construction: AppsFlyer
• Attribution/deduplication: AppsFlyer
• Deep linking: send the user directly back into the relevant app screen

TikTok, for example, explicitly supports app retargeting through MMP integrations including AppsFlyer, Adjust, Branch, Singular and Kochava. ads.tiktok.comliftoff.ai

If you want the simplest answer

I'd start with AppsFlyer + Liftoff.

Liftoff is particularly interesting if your primary objective is performance retargeting outside the walled gardens; its App-to-Web product specifically targets existing in-app users and uses its ML technology to optimize mobile-web conversions. liftoff.ai

Then add Meta and TikTok separately for social reach rather than trying to force a single DSP to cover everything.

One important caveat in 2026: don't evaluate these platforms purely on "can they retarget an app user?" iOS privacy restrictions mean the quality of audience matching and measurement varies substantially by network and OS. AppsFlyer documents different privacy-preserving measurement approaches for Meta, Google, TikTok, Snapchat and non-SRN networks. support.appsflyer.com

If you tell me your app category, monthly retargeting spend, countries, iOS/Android split, and whether the goal is purchases/subscriptions/DAU, I can narrow this down to the best 2–3 vendors and a recommended architecture.

If your goal is retargeting existing mobile-app users across the open web and social, I’d separate the problem into two layers: the retargeting/DSP platform and the social platforms. No single vendor is equally strong at deterministic app retargeting across both open-web inventory and closed social ecosystems.

My shortlist

If I had to pick one starting point: Moloco for the app-retargeting component, paired with Meta + Google for social/open-web reach.

Moloco specifically supports re-engagement campaigns optimized toward app opens, in-app events, and ROAS, and lets you target based on in-app activity and user lists. Its current product claims reach across 2B+ daily active users in 3M+ independent apps. help.moloco.com

Moloco Ads

If "open web" is really important

I'd look at Google Ads and potentially a broader DSP rather than assuming a mobile-retargeting specialist covers websites. This distinction matters: Remerge explicitly says its retargeting campaigns do not run on desktop/mobile websites; it's focused on Android/iOS app environments. help.remerge.io

Similarly, Liftoff is particularly strong in programmatic mobile inventory and app re-engagement. Its current Accelerate product supports re-engagement and ROAS optimization. liftoff.ai

Liftoff Accelerate

The stack I'd actually build

1. AppsFlyer / Adjust / Branch → audience + attribution layer
Use your MMP to define cohorts such as:

• Installed but never purchased
• Purchased 30–90 days ago
• Abandoned cart
• Lapsed 14 days
• High-LTV customers
• Users who haven't opened the app in 30 days

AppsFlyer explicitly supports retargeting attribution for both re-engagement and reinstall/re-attribution. support.appsflyer.com

2. Moloco or Liftoff → programmatic app retargeting

3. Meta → Facebook/Instagram

4. Google → Search/YouTube/Display where appropriate

5. TikTok → incremental social reach

The important thing is to share the same audience definitions and suppression logic across platforms, rather than letting each ad platform independently decide who is "a customer."

One major caveat in 2026

Don't evaluate vendors solely on their historical ability to do deterministic ID-based retargeting. Privacy changes have made device-level targeting substantially harder, particularly on iOS. For example, Moloco's documentation notes that when users limit ad tracking and the advertising ID isn't available, those users can't be deterministically retargeted by device ID. help.moloco.com

That's why I'd put substantial weight on first-party event data, MMP integration, consent/privacy handling, incrementality measurement, and modeled audiences, not just claimed inventory reach.

Bottom line:

• Best dedicated app retargeting: Moloco
• Best alternative: Liftoff
• Best specialist: Remerge
• Best social: Meta
• Best open-web/YouTube complement: Google
• Best overall architecture: MMP + Moloco/Liftoff + Meta + Google, with centralized suppression and incrementality measurement.

If you tell me your app category, monthly active users, target geographies, and approximate monthly retargeting budget, I can narrow this down to the 2–3 platforms I'd actually test and how I'd split the budget.

If your goal is retargeting existing mobile-app users across both the open web and social, I’d avoid looking for a single “retargeting tool” and instead build around an MMP + channel-specific buying platforms.

My shortlist

What I'd choose

For most companies: AppsFlyer + Criteo + Meta + Google + TikTok.

AppsFlyer should be your audience/measurement layer. Its Audiences product can build segments from app behavior, revenue, geography, device, attribution source, etc., and connect them to paid channels. support.appsflyer.com

Then:

• Criteo for open-web + in-app programmatic retargeting, particularly if you're e-commerce/marketplace. Criteo explicitly supports app retargeting across mobile web and in-app environments, and its broader offering spans open web, social, video and in-app inventory. help.criteo.com
• Meta Ads for Facebook/Instagram. Meta supports app-based Custom Audiences and retargeting based on in-app actions through its SDK. www.facebook.com
• Google Ads for Google/YouTube/web inventory. Google supports dynamic remarketing based on app activity and can use app events to tailor audiences across web and app inventory. support.google.com
• TikTok Ads for TikTok. TikTok currently supports app retargeting using MMP integrations including AppsFlyer, Adjust, Branch, Singular and Kochava. help.criteo.comads.tiktok.com

If you're primarily a mobile app company

I'd seriously test Moloco.

Moloco Ads is purpose-built for app acquisition and re-engagement, with optimization toward app opens, in-app events and ROAS. Its current platform reaches users across a large independent mobile-app ecosystem. help.moloco.com

It's particularly interesting if you're trying to bring dormant/high-value users back, rather than simply reminding everyone who installed your app to open it.

One important caveat

Don't expect one platform to literally give you Facebook + Instagram + TikTok + the entire open web through one buying interface. Social platforms are largely walled gardens.

A good architecture is:

App → AppsFlyer/Adjust → audience segments →

• Meta → Facebook/Instagram
• TikTok → TikTok
• Google → Google/YouTube/display
• Criteo or Moloco → programmatic/open-web & app inventory

Your segmentation should be behavioral, e.g.:

• Installed but never opened
• Opened but didn't register
• Registered but didn't purchase
• Added to cart but abandoned
• Purchased once, no purchase in 30 days
• High-LTV users
• Churn-risk users
• Dormant 30/60/90+ days

If you tell me your app category (e-commerce, fintech, gaming, subscription, marketplace, etc.), monthly ad spend, and whether you're on iOS/Android/both, I can narrow this down to the 2–3 platforms I'd actually buy.

For retargeting mobile app users across the open web + social platforms, the best software depends on whether you need audience management, programmatic reach, attribution, or just paid social retargeting. A typical mature stack uses more than one tool.

Best overall stack for most app companies

My shortlist by company stage

Early-stage app (under ~100k MAU)

• AppsFlyer or Adjust for attribution/audiences
• Meta + Google + TikTok remarketing
• Basic lifecycle messaging (push/email/SMS)

Growth-stage app (100k–10M MAU)

• AppsFlyer Audiences or Adjust Audience Builder
• Remerge or Liftoff for programmatic retargeting
• Meta Advantage+ retargeting campaigns
• Deep linking via AppsFlyer OneLink or similar so ads open the right screen in-app www.appsflyer.com

Large app / subscription / marketplace

• Customer data platform (CDP) + MMP + DSP combination:
  • MMP: AppsFlyer/Adjust
  • CDP: Segment, mParticle, Braze, etc.
  • DSP: Remerge, Liftoff, Moloco, Criteo
  • Social: Meta, TikTok, Google

Important capabilities to look for

Make sure the platform supports:

• Event-based audiences

Examples:

• installed but never opened
• opened 7+ days ago
• abandoned cart
• viewed product but didn’t purchase
• churn-risk users
• high-LTV users

• Deep linking
  • Ad → app → exact product/content screen, not just the home page www.appsflyer.com

• Incrementality testing
  • Retargeting often looks better than it really is because you may be advertising to users who would return anyway.

• Privacy support
  • Especially for iOS (ATT/SKAdNetwork constraints) and changing cookie environments.

If I had to pick one setup

For a serious mobile app marketer today:

AppsFlyer (audience + attribution) + Meta/TikTok/Google retargeting + Remerge or Liftoff for open-web/programmatic reach would be a strong default architecture. www.remerge.iowww.appsflyer.com

If you tell me your app category (gaming, ecommerce, fintech, subscription, marketplace, etc.), monthly active users, and ad budget, I can narrow this to a more specific stack.

If your goal is specifically retargeting existing mobile-app users across the open web + social, I’d look at this as a stack, rather than expecting one platform to do everything.

My shortlist

If I had to pick one for your exact requirement, I'd start with Criteo. Its current app-retargeting product can reach existing app users across mobile web and in-app environments, while its broader platform supports premium open-web and social inventory. help.criteo.com

Criteo Mobile App Advertising

The important distinction

Don't confuse app retargeting with simply uploading a customer list to Meta or Google.

For proper app retargeting, you want to be able to:

• Build audiences from in-app events — e.g. viewed product, added to cart, purchased, lapsed.
• Exclude recent purchasers or other cohorts.
• Deep-link the ad directly into the relevant screen/product in the app.
• Measure re-engagement and re-attribution, not just clicks.
• Coordinate attribution across your paid channels.

AppsFlyer, for example, explicitly supports retargeting attribution for both re-engagement of installed users and re-attribution of users who previously uninstalled the app. support.appsflyer.com

AppsFlyer Retargeting Attribution Guide

What I'd build

AppsFlyer (measurement) + Criteo (programmatic) + Meta/Google (social/search ecosystems) is a sensible setup for a serious app-retargeting program.

Criteo is particularly interesting if you want to go beyond Meta/Google's walled gardens: its app-retargeting setup supports custom app-event audiences and can deliver across mobile web and apps. help.criteo.com

If you're e-commerce, I'd put Criteo and RTB House higher on the list because dynamic product-level retargeting can be very powerful. RTB House specifically positions its product around personalized retargeting across web and app environments. www.rtbhouse.com

If you're a consumer app with lots of behavioral/LTV data, I'd also evaluate Moloco. Its platform is specifically built around acquiring and re-engaging high-value app users with ML optimization.

Bottom line:

• Want one programmatic platform: Criteo
• Want maximum Meta/Instagram reach: Meta
• Want YouTube + Google Display: Google Ads
• Want app-native ML optimization: Moloco
• Want measurement/attribution: AppsFlyer
• Want a performance-focused programmatic alternative: RTB House

If you tell me your app category, monthly retargeting budget, iOS/Android split, and whether you need web and in-app inventory, I can narrow this to the 2–3 platforms I'd actually test.

If your goal is retargeting existing mobile-app users across both the open web and social platforms, I’d think about this as a stack, not a single tool.

My shortlist

If I were choosing today:

• Best overall architecture: AppsFlyer + native social platforms + a retargeting DSP
• Best single platform for an omnichannel setup: Kochava
• Best dedicated mobile retargeting DSP: Liftoff
• Best specialist for mobile-app retargeting: Remerge

The important distinction

If by "open web" you mean mobile websites + desktop websites, be careful with the dedicated mobile retargeting DSPs.

For example, Remerge explicitly says its retargeting campaigns do not run on desktop/mobile websites; its strength is identifying and retargeting users in mobile-app inventory. help.remerge.io

Liftoff is similarly very strong for app re-engagement, using behavioral signals and ML to bring inactive users back into the app. liftoff.aisupport.appsflyer.com

For a genuinely open-web + social + app strategy, I'd therefore lean toward Kochava or AppsFlyer as the audience/measurement backbone, then activate those audiences through the appropriate media channels. Kochava specifically supports audience creation/syndication and omnichannel measurement across app, web, CTV, social and other channels. www.kochava.com

AppsFlyer is particularly good if you already use it as your MMP: its Audiences product lets you create behavioral segments and connect them to paid/owned partners, while its retargeting measurement handles re-engagement and re-attribution. support.appsflyer.com

What I'd build

For a typical consumer app, I'd use:

App → MMP/CDP → audience segments → activation

For example:

• AppsFlyer — source of truth for app events and attribution
• Segment users such as:
  • installed but never purchased
  • purchased once, no purchase in 30 days
  • high-LTV customers
  • abandoned checkout
  • lapsed users
  • churn-risk users
• Meta / Instagram, TikTok, Google/YouTube, etc. — native social/video retargeting
• Liftoff or another DSP — programmatic mobile/open-in-app inventory
• Kochava/AppsFlyer — measurement and audience synchronization

The big caveat in 2026 is identity/consent availability, particularly on iOS. Deterministic device-ID retargeting is much more constrained than it used to be, so you want a vendor with privacy-preserving measurement and audience activation rather than choosing purely based on inventory volume. AppsFlyer, for example, now documents probabilistic modeling, install-referrer matching and deep linking as alternatives when advertiser IDs aren't available. support.appsflyer.com

If you tell me your app category (e-commerce, fintech, gaming, subscription, travel, etc.), monthly active users, and approximate monthly retargeting budget, I can narrow this to the 2–3 platforms I'd actually shortlist and explain why.

If your goal is retargeting existing mobile-app users across both the open web/in-app inventory and social platforms, I’d build the stack around an MMP + several media platforms, rather than expect one tool to do everything.

My shortlist

What I'd actually use

AppsFlyer + Criteo + Meta + TikTok + Google, with Moloco or Liftoff added if you need more scale/performance.

AppsFlyer is useful as the measurement/audience layer: its current retargeting system supports re-engagement and re-attribution, and its Audiences product can synchronize behavior-based segments across 140+ partners, including Meta, Google, TikTok, Criteo, Remerge and Moloco. support.appsflyer.comwww.appsflyer.com

For open-web/mobile-web + in-app inventory, Criteo is particularly relevant. Its app-retargeting product can serve personalized display/video ads across mobile web and in-app environments and use an MMP such as AppsFlyer, Adjust, Branch, Kochava or Singular for measurement. help.criteo.com

For social, run the platforms directly. TikTok explicitly supports app retargeting using AppsFlyer, Adjust, Branch, Singular or Kochava, including in-app-event optimization and deep links. ads.tiktok.com AppsFlyer currently lists Meta, Google, TikTok, Snapchat and other major networks as self-reporting networks. support.appsflyer.com

Moloco vs. Liftoff: I'd test both if you're performance-oriented. Moloco requires MMP attribution configuration and is designed around using mobile behavioral signals for ad optimization. help.moloco.com Liftoff has a dedicated re-engagement product aimed specifically at bringing inactive/deleted app users back. liftoff.ai

One important caveat

Don't judge these platforms by their reported ROAS independently. Meta, TikTok, Criteo, Moloco, etc. can all claim overlapping conversions. Your MMP should be the source of truth and deduplicate the conversions before you compare channel performance. AppsFlyer specifically highlights this problem with multi-partner remarketing. support.appsflyer.comwww.appsflyer.com

If you tell me (1) iOS vs Android, (2) app category, (3) monthly retargeting budget, and (4) whether you want to retarget purchasers, lapsed users, or all installers, I can narrow this to the 2–3 platforms I'd actually buy traffic from and explain how I'd split the budget.

If your goal is specifically retargeting existing mobile-app users across both the open web/in-app inventory and social, I’d shortlist these:

What I'd actually build

1. AppsFlyer → audience/data layer

Use AppsFlyer Audiences to create segments such as:

• Installed but never purchased
• Purchased once, no purchase in 30 days
• High-LTV customers
• Abandoned checkout
• Lapsed users
• Users who completed event A but not event B

AppsFlyer says its Audiences product can build segments from in-app activity, revenue, attribution source, geography, device type, etc., and connect them to paid/owned channels. support.appsflyer.com

2. Moloco → programmatic retargeting

This would be my first choice for the open/in-app programmatic side. Moloco specifically offers re-engagement campaigns optimized for app opens, in-app events and ROAS, and says its inventory reaches billions of daily active users across millions of apps. www.moloco.com

Moloco Ads

3. Meta → Instagram/Facebook

Run your highest-value segments through Meta Custom Audiences. Meta supports retargeting people who have engaged with your app and can optimize app campaigns toward post-install actions. www.facebook.com

Meta for Business

4. Google → YouTube + Display

Google's app remarketing supports reaching people based on interactions inside the app across Google's web/app inventory, with event-based segmentation and personalized messaging. support.google.com

Google Ads

Where Remerge fits

I'd test Remerge vs. Moloco if retargeting is a major part of your growth strategy. Remerge is purpose-built around app retargeting, with real-time audience segmentation based on in-app behavior and a large in-app publisher network. www.remerge.io

Remerge

My recommendation

If you're a serious app-growth team, I'd start with:

AppsFlyer + Moloco + Meta + Google

rather than looking for one platform that does everything.

The important distinction is that "open web" and "mobile in-app" aren't the same inventory. Moloco/Remerge are particularly strong for app-centric programmatic inventory, while Meta and Google give you their respective social/video/web ecosystems.

If you tell me your app category (e-commerce, fintech, gaming, subscription, travel, etc.), monthly ad spend, iOS/Android split, and whether you use AppsFlyer/Adjust, I can narrow this down to the best 2–3 platforms and a recommended retargeting stack.

If your goal is retargeting existing mobile-app users across both the open web and social, I’d shortlist these:

My recommendation: Criteo

For the specific combination you described, Criteo is probably the closest fit. Its app-retargeting product can reach existing app users on mobile websites and inside other apps, while its broader platform supports open-web, video and social inventory. help.criteo.com

More importantly, Criteo now has cross-channel campaigns combining open-web inventory with Facebook/Instagram, with unified campaign management and reporting. help.criteo.com

Criteo Mobile App Advertising

Where AppsFlyer fits

I wouldn't think of AppsFlyer as the primary media-buying platform. I'd use it as your MMP/audience and attribution layer alongside your media partners.

AppsFlyer Audiences can build segments based on things like in-app behavior, revenue, geography, device and attribution source, then connect those audiences to paid channels. support.appsflyer.com It also handles retargeting attribution and deep linking, including distinguishing re-engagement from re-attribution after an uninstall/reinstall. support.appsflyer.com

AppsFlyer Audiences

A practical stack

If I were setting this up today:

AppsFlyer → audience segmentation/attribution → Criteo → open web + Meta

Then use Meta directly if Facebook/Instagram is important enough to warrant dedicated campaigns.

The key is to create audiences such as:

• Installed but never purchased
• Cart/checkout abandoners
• Purchased 30–90 days ago
• Lapsed users
• High-LTV customers
• Users who haven't opened the app in 7/30/90 days

And make sure the ads deep-link back into the relevant screen of the app, rather than dumping users at the app's home screen. AppsFlyer's OneLink supports these retargeting/deep-linking journeys across web and social. support.appsflyer.com

Bottom line: If you want one platform that most closely matches “retarget my app users across open web + social,” start with Criteo. If you're running a serious app-growth program, pair it with AppsFlyer for audience management, attribution and deep linking.

If you tell me your app category, monthly retargeting spend, iOS/Android mix, and whether you need Meta/TikTok specifically, I can narrow this down to the best 2–3 options and compare likely costs, reach, and setup complexity.

If your goal is retargeting existing mobile-app users across the open web and social, I’d separate the problem into two pieces: programmatic retargeting and social retargeting. There isn't one platform that is equally strong at both.

My shortlist

My first choice: Moloco. Its current Re-engagement product is specifically designed to reactivate existing/lapsed app users, and it can reach users across roughly 2.8M independent apps. www.moloco.com

Moloco Ads

Liftoff would be my second choice, particularly if you're doing substantial mobile performance marketing. Its Accelerate platform supports both acquisition and re-engagement and has direct access to major ad exchanges. liftoff.ai

Liftoff Accelerate

Remerge is excellent if your primary objective is sophisticated app retargeting—dynamic creative, behavioral segmentation, re-engagement, etc. The important caveat is that Remerge says it doesn't run retargeting on desktop/mobile websites, so it isn't the answer if "open web" is a hard requirement. www.remerge.io

Remerge

What I'd actually deploy

For a serious consumer app, I'd probably run:

Moloco/Liftoff → open-web & in-app programmatic
Meta → Facebook + Instagram
Google → YouTube + Google ecosystem
AppsFlyer/Adjust/Branch → measurement, audiences and attribution

The MMP piece matters: platforms such as Moloco require an MMP integration to receive app events and properly measure/optimize campaigns. help.moloco.com AppsFlyer also recently expanded its positioning around omnichannel measurement across mobile, web and CTV. www.axios.com

So if you mean "I have a list of users who have installed my app, and I want to reach those same people on websites, other apps, Facebook/Instagram, etc.", I'd start with Moloco + Meta + an MMP, rather than looking for a single all-in-one DSP.

If you tell me what kind of app (e-commerce, fintech, gaming, subscription, marketplace, etc.), monthly retargeting budget, and iOS vs. Android mix, I can narrow this to the best 2–3 platforms and explain the likely tradeoffs.