Kotlin documentation, offline on Android

The Kotlin standard library API, downloaded to your phone and searchable without a connection. Check the exact behaviour of windowed, associateBy or buildList without opening a browser.

Get it on Google Play See example entries

What is in the Kotlin docset

This docset is the API reference of the Kotlin standard library (kotlin.collections, kotlin.text, kotlin.sequences, scope functions such as let and apply, and the rest of stdlib). It comes from the community-contributed catalogue, where the current build is version 1.9.20.

Two honest limits: the docset is the standard library, not the language guide, and kotlinx.coroutines is not part of it. For Android APIs written in Kotlin, install the separate Android (Kotlin) docset.

Version: 1.9.20
Entries: 12,301
Download: 91.1 MB
Source: Community-contributed docset

Entry types: Property 6,887 · Function 3,516 · Class 749 · Constructor 732 · Interface 317 · Enum 65. Figures from the docset's own index, checked on 27 October 2026; versions change as the feeds update. Download size is the compressed archive.

Illustration with real entries from the Kotlin docset.

Example entries you can search offline

A few real entries from the Kotlin docset's index, as they appear in search results:

Entry	Type
listOf	Function
mapNotNull	Function
groupBy	Function
associateBy	Function
buildList	Function
windowed	Function
chunked	Function
takeIf	Function
Result	Class
Regex	Class

How to get the Kotlin documentation offline

Install DevDocs from Google Play. It is free and needs no account.
Open the Store tab and search for Kotlin.
Tap Download. The docset downloads in the background (91.1 MB compressed) and is indexed on your phone.
Open Search or the docset in your Library. From now on it works with no connection.

Tips for searching the Kotlin docs

Many collection functions have several overloads (for List, Sequence, Map…). They show as separate results; the docset name under each result helps you pick.
Install Kotlin together with Android (Kotlin) and Java: one search then covers all three, which is handy when a Java API is called from Kotlin.
Use the reader's font size and reading-width settings for long signatures on a small screen.

Related docsets

Also in the DevDocs Store: Android (Kotlin), Java, Gradle DSL, Gradle User Guide. Install any of them and one search covers them all. See also: Android documentation offline and Java documentation offline.

Kotlin docs offline: questions

Is this the latest Kotlin version?

No. The community catalogue currently publishes Kotlin stdlib 1.9.20. Most of the standard library is unchanged since then, but newer additions will be missing until the catalogue is updated.

Are coroutines included?

No. The docset covers the standard library only; kotlinx.coroutines is not in it and there is no separate coroutines docset in the catalogue today.

How big is the download?

About 91 MB compressed. It takes more space once unpacked, and DevDocs shows the storage used per docset.

Get the Kotlin docs on your phone

DevDocs is free, has no ads and needs no account.

Get it on Google Play