What is API 19 in Android?

Android api level 19 means the android os version (kitkat) . It contains the standard android packages(from Android Open Source Projects). But the google api 19 is the android api 19+ google api’s like google settings and other packages provided by google.

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What is the target sdk version?

android:targetSdkVersion — Specifies the API Level on which the application is designed to run . In some cases, this allows the application to use manifest elements or behaviors defined in the target API Level, rather than being restricted to using only those defined for the minimum API Level.

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