Cipher given the version of Android.Cipher that works for the API ≥ 18.Cipher that works for the legacy API 9 to 18.Cipher that works for API ≥ 23.RSA) in the Android Keystore.CipherClient.encrypt(String) to decrypted it
using the Android Key Store.SyncCrypto.encrypt(String).AES key.SyncUser by decrypting first the serialised Json.SharedPreferences.SyncUser) using Android built in KeyStore capabilities.SyncCrypto methods for API 18 (after the Android KeyStore public API).SyncCrypto methods for API 23 (after the Android KeyStore public API), using
the introduced KeyGenParameterSpec.SyncCrypto given the version of Android.SyncCrypto methods for API 9 to 18 (pre Android KeyStore public API).Intent that will help define or unlock the KeyStore.Intent
to start the platform system Activity to create/unlock the KeyStore.