Login with OTP over mobile number is possible via miniOrange 2fa ‑ passwordless login Application . You can allow customers to Login / Signup with Mobile number . Also, you can allow customers to enable two -factor authentication and allow them to login with the combination of username-password and two factor (OTP over email/SMS , Google Authenticator, Push Notification , Security Questions , etc. ) Checkout more information about their application here
Yes it absolutely possible customers can login on store with phone number instead of using email address. Try this Shopify login with phone number app and offer a wonderful shopping experience to customers. You can simply enter their phone number after an OTP code enter he/she can order desired products. It helps to boost the repeat orders due to an efficient login process. The admin can hide the old registration form, customize text phone and login button.