Best option to store username and password in android app

Question

I am developing an Android app where the user needs to sign in to perform operations. But mostly on an android handset, people use \"Keep me signed in\", In

Answer 1

Using NDK for encryption and decryption along with defining the String Key variable there instead of saving it in the shared preferences or defining it ins the string xml would help to prevent secret key stealing against most of the script kiddies. The resulted cipher text would be then stored in the shared preferences. This link may help about the sample code