A temporary code, usually sent by SMS or an app, used once to confirm identity or approve a sensitive action.
OTP stands for one-time password. It is a short code, often 4 to 6 digits, valid for a short time and a single use. It can be sent by SMS, WhatsApp or email, or generated in an authenticator app. It is used for signing in, verifying a phone number or approving an important action.
Phone sign-in with an OTP is very familiar to customers in the region and spares them from remembering passwords. But it has messaging costs and needs protection from abuse, such as bots requesting thousands of codes. Fanann supports phone sign-in as part of its managed database.
Practical tip: limit how many codes can be requested per number and per device within a time window, and make codes expire quickly. Show a clear message if the code does not arrive, with a resend option after a short wait.