Your store listing is shelf space, and the description is 4,000 characters of it — identically generous on both major stores. But the rules for spending those characters are opposite. Apple does not search your App Store description at all; Google's Play algorithm lives in yours. Get that split wrong and you will do App Store Optimization on the wrong surface, stuffing keywords where they are ignored and writing pure ad copy where the algorithm is listening. Here is the developer's map.
The limits side by side
Both stores count characters with spaces included, and both refuse the field outright when you cross the cap. The full comparison, as of 2026:
| Field | App Store (Apple) | Google Play |
|---|---|---|
| App name | 30 characters | 30 characters |
| Short summary text | Subtitle: 30 characters | Short description: 80 characters |
| Full description | 4,000 characters | 4,000 characters |
| Keywords | Hidden keyword field: 100 characters | No separate field — description is indexed |
| Promotional text | 170 characters | No equivalent |
The identical 4,000-character descriptions are the trap: they invite copy-paste listings, and a copy-paste listing is optimized for exactly one of the two stores.
The ASO difference: Play indexes your description, Apple doesn't
This is the single most consequential fact in store listing copy. On Google Play, the text of your description feeds search indexing — the words you write influence what queries your app surfaces for, which makes the description both conversion copy and discovery surface. On the App Store, the description is not part of the search index: what Apple matches against searches is your app name, your subtitle, and the hidden 100-character keyword field. The App Store description has one job — converting the human who is already looking at the page.
Same 4,000 characters, two different jobs. Write Apple's description for the reader and put your keyword effort into the fields Apple actually reads; write Play's description for the reader and the algorithm, with your core terms present, natural, and early.
Spending your App Store characters
Four fields, four jobs:
- Keyword field (100 characters, hidden). Comma-separated single words, no spaces after commas, no duplicates of words already in your name or subtitle — those are wasted characters. Never competitor names or trademarks; that is a rejection.
- Subtitle (30 characters). A second indexed field that must also read as a value line to humans — "Word Counter & Reading Time" works as both.
- Promotional text (170 characters). Updatable instantly, without waiting on App Review — the right home for launch announcements and limited-time offers.
- Description (4,000 characters). Only the first few lines are visible before "more", so lead with the pitch. Do not stuff keywords here — on Apple it is wasted, and it makes the page read badly to the one audience it serves.
Spending your Play Store characters
Google Play has no hidden keyword field, so the visible text is the metadata. The short description (80 characters) is the highest-ASO-weight field after the title: it appears above "Read More" in the listing, so front-load the core term and make the rest a benefit. In the full description (4,000 characters), put your main keywords in the first lines, then repeat each core term naturally a handful of times across the full text — a few mentions in a roughly 600-word description keeps you near the healthy 1–2% keyword density band, while pushing well past that reads as stuffing to the algorithm and to readers alike. Play's search has grown semantically sophisticated: related terms and entities count, so natural language beats exact-match repetition.
The stuffing trap on both stores
Because the caps are high, the temptation is to fill them, and both stores punish the same failure differently. On Google Play, a description that repeats "fitness tracker workout planner fitness app fitness" reads as spam to the indexing system, and the same block of unrelated keywords tacked onto the final paragraph — the classic "keyword footer" — has violated Play policy outright for years. On the App Store, stuffing the description is simply wasted ink because nothing in it is indexed, while stuffing the 100-character keyword field with plural variants and duplicates burns the only searchable budget you have. The shared fix is the one that also writes best: cover the topic the way a knowledgeable friend would, name the core terms the way people actually search them, and stop. A description written for a smart reader is almost always within the healthy band before you ever count.
One master description, checked against both caps
In practice: draft one master description, localize it, then spin store-specific versions — keyword-forward for Play, pitch forward for Apple. Before you submit, paste each variant into the WordlyCount character counter and check the live character count against the 4,000, 80, 170, 100, and 30 caps — word processors count words, not characters, and every one of these fields is a character budget. The same budgeting discipline applies across your whole launch surface, from the short-copy rules in Google Ads character limits to the listing caps in YouTube character limits if video is part of the plan.