OBB files: what they are and where to put them

What an OBB is

An OBB (opaque binary blob) is the expansion file format Google Play uses for apps larger than its APK size limit. The APK holds the code; the OBB holds assets such as textures, audio and level data. A game may have a main file and a smaller patch file. Modern games increasingly download their data inside the app instead, but thousands of titles still ship OBBs.

Naming and location

The file name encodes the version code and package name: main.70382.com.example.game.obb. It lives at

Android/obb/com.example.game/main.70382.com.example.game.obb

on internal storage. Both the folder name and the file name must match the package and version exactly. A game whose version code changes needs the OBB for that version; an old file is ignored.

How it gets there

• Google Play downloads it with the app.
• XAPK installers (APKPure app, SAI) extract it from the bundle and place it during installation.
• Manual copy: extract the XAPK as a zip, find the Android/obb/... folder inside and copy it to the same path on the device.

The Android 11 restriction

Since Android 11, ordinary apps cannot write to Android/obb or Android/data for other packages. File managers either request All files access (which many are not allowed to have) or fail silently. The reliable ways are an installer app that uses the system's installation session, a computer over USB or adb push, or the Files app's SAF picker, which some file managers use to get access to that folder.

Symptoms of a missing or wrong OBB

• The game starts, shows a loading screen or a black screen, then closes.
• The game begins downloading gigabytes on first launch even though you installed a full bundle.
• An "expansion file not found" or "verification failed" message.

Check that the folder exists, the file name matches the installed version code (see finding the version code), and the file size matches the download page. Reinstalling with an XAPK installer fixes almost every case.