Android developers can now build apps as large as 4GB for Android Market after previously being limited to 50MB, to allow for more complex products.

A post on the Android Developers blog said that although most apps benefit from being smaller as anything larger can be harder to download, some specialist titles, such as 3D interactive games, require more on-device resources.

The maximum size of application package files available from the store will remain 50MB – to make sure they can be securely stored on devices – but developers can now attach a maximum of two expansion files, each up to 2GB in size and in any format. Google is providing sample code and libraries for expansion files in the Android SDK Manager.

Android Market will host the files and users will see the total size of apps before they purchase and install them. On most new devices, the expansion files will be automatically downloaded and the refund period for the app won’t start until they have been completely downloaded. Older devices will download the expansion files the first time the app runs.