
How Indexing in App Stores Works: Cross-locales, Irrelevant Keywords, and Branded Ones
We’ve already explained in detail how indexing works in App Store and on Google Play and studied the difference in their algorithms. In this article, we’ll pay more attention to the intricacies. Let’s talk about cross-locales, branded keywords and ‘free’ keywords, indexing by irrelevant queries, and other details.
Why are stores indexing apps by irrelevant queries?
You may have noticed that the indexing may include keywords not only from metadata like title, short description, or other text elements, but also any other queries, and sometimes they may seem weird and irrelevant. That can be due to algorithms.
On Google Play, apps are indexed by AI that identifies relevant keywords based on app category, tags, keywords in metadata for all localizations, reviews, etc.
In App Store, keywords from different metadata are combined to make keyword variations. Keywords with typos, special symbols, queries relevant for your category, and competitors data can be indexed too. Those keywords can be up to tens of thousands.

How does Checkaso parse the data?
Every day we collect the data on all keywords added to Checkaso and available in the database. We collect them directly from stores and frequently update the data like ranking, hints, Search Volume, etc. Besides, we look for search results for every keyword, that is, apps that stores show to users. This also means that we check if an app is displayed among the search results by certain keywords (both tracked and those of competitors).
How to use global metadata indexing on Google Play and in App Store?
Google Play indexes metadata across all localizations. Because of this, it can show your app in some locale by keyword in another language. That’s pretty weird, right? But useful. Say you’re promoting your app in a single country. To optimize the metadata of other localizations, you can use relevant keywords in the desired language. This will boost indexing and ranking in your target country.
The App Store indexing algorithm is more primitive. It simply combines all the words from the title, subtitle, and keyword fields. It cannot distinguish between cases, plural and singular nouns in languages other than English. That’s why, when collecting the metadata, you may want to use keywords in a proper form right away. English is the only exception that makes it possible to save some characters. For example, a singular noun may suffice for the algorithms to index the plural one as well.
Make use of additional locales. In some countries, there are several official languages. Accordingly, there are two locales in the United States — English (US) and Spanish (Mexico). You can add two languages for the country. This way, you’ll target more queries and reach a larger audience. English (UK) is indexed in all countries except the United States, Japan, and Canada. It can be used as an additional resource for the keywords you want. Please keep in mind that keywords can be combined only for the same locale. This means that, if you have ‘bubble’ as a keyword for Spanish (MX) and ‘shooter’ for English (US), then you won’t get indexed by ‘bubble shooter’ in the US.

Here is the full table that shows you what locales you can add to increase the number of available keywords.
By what keywords do the stores index apps by default?
There is a conditional list of ‘free keywords that don’t have to be included in the App Store metadata. The stores are believed to index by them a priori. Hence, they’re not worth wasting precious metadata space. But, just to be clear, experimenting is the best choice. Some ASO specialists prefer to play it safe and for good reason.
This can be illustrated by the recent case as App Store stopped indexing some apps by queries that included the word “free”. Those apps that played it safe and added the word to their keywords fields stayed while others disappeared from the radar. That was temporary, but it clearly had quite an impact on conversion. As a reminder, according to Apple’s rules, the word “free” (or its equivalent in any language) may not be added to app title and subtitle.
Below is a list of keywords that you don’t have to add to your metadata. It’s relevant to English. Other languages are a challenge yet. By analogy, we can assume that queries with function words, pronouns and different verb forms will also be automatically indexed. Anyway, it might be better to stick to safe solutions and keep experimenting.

How to use branded keywords?
Branded keywords are not allowed to be used in metadata. But there are many loopholes to this rule.
Say, you have an Instagram Stories editor app. In this case, you have the right to mention the brand. After all, your functionality is connected with Instagram and it’s not your direct competitor. If you’re openly competing with someone, then you cannot enter their brand in your metadata. Google Play reviewers will most likely “cancel” your app, while App Store will cut out certain keywords. Well, your competitor can file a complaint too.
- You can enter keywords in the invisible metadata (keywords field) in App Store.
- Black hat ASO specialists can enter branded keywords in reviews, the developer’s name, or promoted IAP titles in App Store.

If the brand name is a common word, it can be used too. The main issue here is that the context makes it clear why you use it.
P.S.
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