The app is asking me to scan my encryption key when I try to log into my account. What does this mean?

Whenever a user creates an account, an encryption key under the form of a QR code is emailed to them. This is the equivalent of a two-factor authentication process (2FA) that will be required whenever you are logging into your account from an unknown device. To access your account, scan this encryption key with the new device and you should then be able to log in.

Can't find your encryption key? Head into "Menu" > "Settings" > "Account & Security" > "Show Account Key" > "Send by email".