Install the app and sign in with the same account: your access, your answers and your progress come back with it.
Sign in with the e-mail address of your account: we email you a code, or you tap the link in that mail. Your answers and progress are kept in your account, so your plan carries on where it was, and the mock exams you handed in appear on the new phone too.
Bought in the App Store or on Google Play? Tap «Restore purchases» in Me.
No password is needed. If your account has one from before, you can still use it with «Use my password»; forgotten it? «Forgot your password?» sends a link to your e-mail address, and setting a new password signs you out on every other device.
Signing in needs a connection. Signing in on the new phone does not sign out the old one: to do that, see «Signing out a lost device».