<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    android:installLocation="auto"
    ... >

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    android:installLocation="preferExternal"
    ... >

http://developer.android.com/guide/appendix/install-location.html

If you declare "preferExternal", you request that your application be installed on the external storage, but the system does not guarantee that your application will be installed on the external storage. If the external storage is full, the system will install it on the internal storage. The user can also move your application between the two locations.

If you declare "auto", you indicate that your application may be installed on the external storage, but you don't have a preference of install location. The system will decide where to install your application based on several factors. The user can also move your application between the two locations.

allow android apps install on external device

android

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