Google App Campaigns Creative Specs: Every Asset and How to Use It

Google App campaigns (still widely called UAC, from their old name Universal App Campaigns) do not ask you to build ads. They ask for assets: lines of text, images, videos and HTML5 files, plus your store listing. Google's system then assembles ads from those parts for Search, Google Play, YouTube, the Display Network and its partners, and learns which combinations work. Your creative job is therefore to supply good parts, in every shape Google might need, and to replace the weak ones over time.

The specs below are from Google's own Ads Help pages as of October 2026. Google changes them occasionally, so check the linked help article before a large production run. For the playable side in depth, see Google UAC playable ads.

How App campaigns use your creative

You do not choose placements or write individual ads. You add assets to an ad group, and Google mixes them: a headline with an image for a Display slot, a video for YouTube, an icon and a line of text for Search and Google Play. Some parts come straight from your store listing, including the app icon, screenshots and title. If you supply no video, Google may generate one from your other assets and your listing, and it rarely looks as good as one you made.

The consequence for production is simple: missing formats are filled automatically or not served at all, so a full set of assets in every orientation is the cheapest way to reach every placement.

Text assets

• Headlines: up to five, each 30 characters or fewer.
• Descriptions: up to five, each 90 characters or fewer.

Text is combined with everything else, so every line has to stand alone. Write each headline as a complete reason to install ("Merge dragons, build an empire") rather than half of a sentence that only works next to another. Vary the angle across lines: one about the core action, one about progress, one about competition, one about a feature, one about the offer. Lines that say the same thing in different words give the system nothing to learn from.

Image assets

Images are JPG or PNG, up to 5 MB each, in three ratios:

• 1:1 square: minimum 200 x 200, recommended 1200 x 1200.
• 1.91:1 landscape: minimum 600 x 314, recommended 1200 x 628.
• 4:5 portrait: minimum 320 x 400, recommended 1200 x 1500.

Supply all three. Design for the smallest size you might be shown at: a busy scene with small text becomes noise in a small Display slot. One clear subject, high contrast and little or no text tends to survive every crop. Do not put a fake button in the image; Google adds its own install button, and an image button that does nothing is a poor experience and a policy risk.

Video assets

Videos are added as YouTube links, so upload them to a YouTube channel first (they can be unlisted). Supply landscape, portrait and square versions: portrait matters most for YouTube Shorts and full-screen in-app slots, landscape for in-stream YouTube, and square for feeds. Google's guidance recommends short videos, and its help pages mention lengths of ten to thirty seconds.

• Show gameplay or the product working in the first two seconds; there is no guarantee the viewer sees second ten.
• Design for silence first. Many placements start muted.
• Make each orientation properly rather than cropping one master. A landscape gameplay capture cropped to portrait often cuts off the action.

HTML5 assets (playables)

HTML5 is how a playable ad reaches App campaigns. Google's current specs are:

• A ZIP of up to 5 MB containing no more than 512 files. Older pages quoted a smaller limit; the current one is 5 MB.
• An orientation declared in the HTML with the ad.orientation meta tag (portrait, landscape, or both).
• Google's Exit API: load exitapi.js and call ExitApi.exit() when the player taps your call to action. Without it, Google adds its own install button.
• No external requests at runtime: every image, sound and script inside the ZIP.
• A pass through Google's HTML5 validator before upload.

Google documents HTML5 assets as serving on the Display Network, alongside your app icon and description, in campaigns for installs; they cannot be used in engagement or pre-registration campaigns. HTML5 is billed on engagement (the viewer's first interaction), and an install within 30 days of that engagement counts as a conversion. That billing model favours playables whose first touch is natural and obvious: a confusing first frame costs nothing, but it also earns nothing.

How many assets to add

Google allows up to 20 each of images, videos and HTML5 files in an ad group, and its guidance is to use as many slots as you can fill well. More good assets give the system more combinations to test; more mediocre ones dilute spend. A practical starting set for a game is all five headlines and descriptions, two or three images per ratio, a video in each orientation, and one or two playables.

Reading asset ratings

Each asset is shown as Learning until it has enough data, then rated Low, Good or Best. The rating ranks the asset against others of the same type in the same campaign, so a Low video is not necessarily bad in absolute terms, only weaker than its neighbours. Use the ratings to decide what to replace, not what to delete in a panic:

1. Wait for ratings to settle before acting; a new asset needs time and spend.
2. Replace Low assets with new ones that test a different idea, not small edits of the same one.
3. Make more of what is rated Best: new variants of the winning hook in other formats and orientations.
4. Keep a record of what you replaced and why, so the next round starts from a lesson.

Campaign subtypes and what they accept

• App installs: the standard subtype, and the one that accepts HTML5.
• App engagement: for bringing existing users back, with deep links. Google requires a meaningful installed base and conversion tracking. No HTML5. See retargeting with playables for the creative side.
• App pre-registration: Android only, for games not yet released. Ads run on Google Play, YouTube and the Display Network. No HTML5. See pre-registration campaigns.

AI-generated assets

Google can now generate image assets for App campaigns, and in some regions ads using certain AI-generated assets carry a disclosure label. Generated assets are useful to fill a missing ratio quickly, but they are built from your listing and know nothing about your best-performing hooks. Treat them as stand-ins until your own assets replace them, and judge them by the same ratings.

A production checklist

1. Five headlines and five descriptions, each a different angle, each complete on its own.
2. Images in 1:1, 1.91:1 and 4:5 at the recommended sizes.
3. Videos uploaded to YouTube in landscape, portrait and square.
4. One or two HTML5 playables as ZIPs under 5 MB, with ExitApi and the orientation tag, checked with the validator.
5. Store listing up to date, since the icon and screenshots come from it.
6. A date to review ratings and replace the weakest assets.

Playable Ads Maker exports a Google-ready ZIP from the same project that exports to the other 12 networks, and our spec checker reads any playable file and reports what Google, or any other network, would object to before you upload.