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What makes a good end card for a mobile game video ad? A seven-point checklist
It repeats the video's promise, shows the game, makes one ask and fits each network's spec. A checklist with AppLovin, Unity, ironSource, Mintegral and Google rules.
TL;DR. A good end card for a mobile game video ad repeats the promise the video just made, shows the game (a character, the board, the moment of play) rather than the logo, and makes one ask with one install button. It is built to each network's own spec and tested as its own variable against the same video, because it is the screen in front of the player when the install decision happens. Below: the seven-point checklist we work from, and the published specs for AppLovin, Unity Ads, ironSource Ads, Mintegral and Google App campaigns.
What the end card is for
Unity's documentation gives the plainest definition: "End cards are creative assets displayed at the end of an ad with a call to action for users to download the advertised product." On Unity Ads it is not optional: "all video ads must also include an end card."
The video earns the attention; the end card asks for the action. In our experience it is also produced last and reused across a whole library, which we covered in end cards are the most under-tested asset you own.
How to build a good end card: the checklist
- Repeat the video's promise. Same hook, same words, same character if there was one. Our rule of thumb: if the video sold a puzzle, the end card shows that puzzle.
- Show the game, not the logo. Avi Cohen of Bigabid, interviewed by Singular, said: "We saw success with characters almost everywhere." Unity's video guidance makes the related point: "It helps user retention if the app experience is what was expected after seeing the trailer."
- Make one ask, and point at it. One install button, large, low on the screen where the thumb is (our rule). Cohen's tip in the same Singular piece: "you could use a finger pointing at the install button." For iOS, Unity adds a hard rule: "only depict the Apple app store logo."
- Build to each network's spec. Sizes differ (table below). Unity warns that "Dynamic cropping might occur" on portrait and landscape images and asks for a 100-pixel buffer from the edges, so keep text and the button inside it.
- If it is interactive, follow the redirect rules. AppLovin says an HTML ad "must not redirect to app stores on the first tap/click" and "Audio must remain muted until the first user interaction." Unity says: "Do not automatically redirect or use the first touch to redirect to the app store." ironSource Ads requires users to interact "at least once before being sent to the app store."
- Keep the promise past the tap. ironSource's documentation says a low conversion rate "could mean that the user is seeing something they weren’t expecting in the store". AppLovin lets you point a creative set at a custom product page (iOS) or custom store listing (Android), so the store can continue what the end card said.
- Test it as its own variable, then test combinations. Our method: hold the video constant, run three end cards (the current default, one that repeats the hook word for word, one that leads with a character or offer), and read installs, not taps. Then check pairings, because, as Cohen put it, "it’s very hard to test it alone without the video". ironSource's advice on order holds: "test more significant variables in the user experience first".
The full guide to end card formats and testing is in end cards: what they are, the specs, and how to test them.
The specs, by network
| Network | Static end card | Interactive end card | Worth knowing |
|---|---|---|---|
| AppLovin | 9:16 image: 320×480, 320×512, 640×1138 or 768×1024, minimum 270×480; GIF, JPEG or PNG, up to 10 MB | One HTML file, 5 MB or smaller, MRAID v2.0, no external requests | Up to 10 files of each asset type can be selected for a creative set |
| Unity Ads | JPG, PNG or GIF, 5 MB; square 800×800 is the default and recommended; 800×600 landscape, 600×800 portrait | One inline HTML file up to 5 MB, MRAID 3.0, portrait and landscape versions | Every video ad needs an end card |
| ironSource Ads | Full-screen images at 9:16 and 16:9 for phones (3:4 and 4:3 tablet images optional), max 2 MB; a carousel end card is also offered | Inline HTML, 5 MB or less; users must interact at least once and for at least 7 seconds before the store redirect | Docs we read are archived snapshots from early 2026; the live pages now redirect |
| Mintegral | "Video&Image Endcard" ad output: 1200×627 image and 512×512 icon required; 720×1280 and 768×1024 among optional sizes | "Video&Playable" ad output pairs a video with a playable | The detailed creative spec sits in a linked document we could not load |
| Google App campaigns | Auto end screen, generated from campaign information: app name, icon, price and an install link | None described | In-stream ads in app install campaigns only; YouTube-created end screens won’t appear when it is on |
A note on names: Unity LevelPlay is Unity's ad mediation product; the advertiser-side end card rules sit under ironSource Ads, in Unity's Grow docs.
On Google's auto end screen there is nothing to design: it is built from information in your campaign, so your app's name and icon do the job a designed end card does elsewhere.
Static or interactive?
The networks lean interactive. ironSource's creative guidance says: "we recommend pairing your videos with interactive end cards (IEC) to increase user engagement." Moloco reports that for its top gaming advertisers "as much as 70% ~ 80% of video spend" is paired with interactive end cards instead of static ones.
ironSource also sets the brief for one: "An IEC should supplement the video it’s paired with", for example by letting users try the gameplay shown in the video.
Our view: find the message with static cards first, since they are fast to vary, then build the interactive version of the winner. On AppLovin, where long videos build to the end, the ending carries even more of the sale; see our notes on AppLovin long-form ads.
When the matching rule breaks
Matching the video is our default, not a law. Singular's write-up of the Cohen interview describes a test of two end cards: one "similar looking, just with a CTA and a logo", the other "completely unrelated and generic". It reports that "the generic-looking end card worked better." One test from one company, but it is why step 7 exists: run the matched card and a contrasting one, and let installs decide.
Where Flixr fits
Flixr makes end cards from the same brief as the video and the landing page, and runs them in clients' ad accounts on AppLovin, Meta and TikTok.
Questions people ask
What size should a mobile game end card be? It depends on the network. AppLovin takes a 9:16 image from 320×480 up to 768×1024 (minimum 270×480), Unity Ads recommends a square 800×800 image, and Mintegral's video and image end card output requires a 1200×627 image. Design one master and export per network.
Should a mobile game ad use a static or an interactive end card? Both, in that order, is our view. ironSource recommends pairing videos with interactive end cards and Moloco reports 70 to 80 percent of top gaming advertisers' video spend paired with them, but static cards are quicker to vary while you find the message.
Should the end card match the video? By default, match the promise. Bigabid's Avi Cohen reported a test where a generic end card beat one built to look like the video, so test both rather than assume.
Can you design your own end card in Google App campaigns? Google's help page describes no uploaded end card for this placement. Auto end screens appear by default after eligible in-stream ads in app install campaigns and show details such as the app's name, icon and price, with an install link.
How do you test an end card? Hold the video constant and run three end cards against it, reading installs rather than taps. Then hold the winning card and vary the video, so you know which half of the ad does the work.
Sources: AppLovin, "Creative specs & guidelines"; AppLovin, "How to create creative sets"; Unity, "End card ad creatives"; Unity, "Static end cards"; Unity, "Playable end cards"; Unity, "Video asset specifications"; Unity, "Video ad best practices"; Unity Grow overview; ironSource Ads, "Interactive end card", "Interactive ad creative requirements", "Creative sets" and "Creative strategy best practices" (archived 2026); Mintegral, API enumeration values; Google Ads Help, "About auto end screens for video ads"; Moloco, "Ad formats driving success in gaming"; Singular, John Koetsier, interview with Avi Cohen of Bigabid, 18 Oct 2024.