Based on  Bazaar regulations, the size of the uploaded APK must not be more than 150MB. For most apps, this amount provides enough space for application codes and assets. However, some apps need more space for high-quality graphic files, media files, and other large assets.

Before, developers had to upload all of their application assets as one APK file, and during updating the app, the large size of the downloading process harmed users’ experience. To solve this problem, Bazaar allows you to upload two large expansion files for each APK.

Each time you upload an APK, you have the option to add one or two OBB files to that APK, and each file can be up to 2GB.

  • The main expansion file, which includes the main assets and additional resources of your app.
  • The patch file, which is optional and you can use it for updating your assets.

One of the significant benefits of using expansion files is the ability to update your application without re-downloading all of the original assets. Bazaar allows you to upload two expansion files for each APK. We suggest you to use the main file for the main and primary assets of your application, which rarely requires updating, and use the patch file for updating and providing new assets. With this process, you don’t need to re-download the main expansion file during update and users will receive updates in a smaller size.

File name format

The expansion files must be in OBB format. Bazaar renames the updated file automatically, using the following scheme:


This scheme includes three components:

main or patch

Specifies whether the file is the main or patch expansion file.


This part must match with the version code of your APK with which the expansion is associated.

You can use one expansion file for different packages of your application, But the version code of the expansion file for different packages does not change and remain the same as the version code of the first APK with which the file is associated.


Your app's package name.

For example, suppose your APK version is 312343 and your package name is The uploaded main file for this APK will be renamed automatically as following:

How to upload the Expansion files:

After applying for a new release and uploading the APKs, by clicking on the … symbol in front of each package, the modal for selecting the expansion file will be open for you.

In this modal, you can select the expansion file from the previously uploaded files or upload new files.

Remember that selecting the patch file will be accessible only after selecting the main expansion file.

Main points:

To upload the expansion file, take notice of the following points:

  • The expansion file must be in OBB format.
  • While updating your app, you can use the previously uploaded expansion files for new APKs.
  • You can have only one main expansion file and one patch file for each APK. Also, you can use one file for several APKs. To support several expansion files in the feature of multiple packages in one release, you must have APKs with different version codes in one release.
  • You can not release an update by changing the expansion files, only. To release an update, you must upload new APKs with upper version codes and attach new files to them. 
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Publish Date: 1400-04-16 12:02

Latest Update: 1400-04-16 12:03