Android minimum app sdk, required sdks for compilation and compatibility issues

Question

I'm new to android and i want make some things clear about some confusions:

If i set my new android application to a minimum sdk version to 4.0.3 (api 15) should i install all sdks between that version and the latest one ? Or should i just install the sdk level same the device/emulator i will use for testing has as plateform version?

What about when i will generate the final apk for the appstore which will be supposed to work in all android platform versions starting from the min sdk i've targeted ?

i was reading about the Android Support Library and i guess it should be always part of the latest sdk. if i use it on my application should i still have earlier sdk versions installed for the compilation ? Won't i never need anymore packages from earlier API version once i use the support library ?

Best regards.

Answer 1

You do not need the SDK for the minimum version. You only need to work with the SDK of the Target/Maximum version.

Download the platform tools and platform through the SDK manager for the Target API version. And if you use features that are not available in the minimum version, use Android Support Libraries.

Answer 2

The purpose of setting your Minimum SDK is to let devices know if they'll be able to run the code based on what SDK they're using. You don't need to have all versions of the SDK, just the most recent one that you're developing for. If you're using Android Development Studio, it will warn you if a feature you're trying to implement is not supported by the Minimum SDK you've set for the project.