Android se izvaja na ogromnem razponu naprav in različic OS ("fragmentacija"), zato morajo aplikacije upravljati s združljivostjo različic — podpirati starejše različice hkrati z varno uporabo novejših funkcij. Razumevanje ravni SDK, knjižnic za združljivost in graceful degradation je pomembno.
Ravni SDK: min, target, compile
minSdk → the OLDEST Android version the app supports (older devices can't install it)
→ lower minSdk = more devices reached, but more compatibility work
targetSdk → the version the app is TESTED/optimized against (and opts into its behaviors)
→ should be kept current (Play requires a recent targetSdk)
compileSdk → the SDK version used to COMPILE (access to newer APIs)
→ Balance: support enough old devices (minSdk) while targeting current behavior (targetSdk).
