To add one: open Settings → Email, enter your address, and confirm it from the link we send. Do this early — it is what makes your account portable between devices.
To change it: use the same screen. Enter the new address, and confirm from the link sent to the new one. Your progress, subscription and history move with you; nothing is reset.
Check your spam folder if the email has not arrived within a few minutes.
Important: change your email before you lose access to the old address if you can. If you have already lost access to it, write to us at info@finoha.net from the new address, include your account ID from Settings → Your account ID, and we will verify and move it manually.