Phone Sign-In and Registration with a Code
The customer signs in with a one-time code - to the phone or to the e-mail - and registers without a password. The sign-in methods are a setting, and the code goes by SMS through the gateway add-on or by e-mail. Sending limits that respect trusted proxies guard the code, a new phone or e-mail is confirmed by a code, and sign-in events go to a log.