After September 27, the oldest version of Android you’ll be able to sign in to is Android 3.0 Honeycomb , which is only for tablets.
Read moreHow do you specify the minimum version of Android required by your application?
For instance, Android 1.0 is API level 1 and Android 4.4 is API level 19. The API level allows you to declare the minimum version with which your app is compatible, using the <uses-sdk> manifest tag and its minSdkVersion attribute .
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