Log In

Log In

1. Using ID

   • Must be unique
     • Extra burden on user to memorize
   • Needs a password
     • Extra burden on user to memorize
   • Easily Forgotten
     • User only uses it when they first sign up or when they change their phone or sim card
   • Useless to Account owner and other Users
     • As a unique ID, the Account owner won't select their own name for their ID
     • Other users would like to name people on their contacts as they like
   • One Centralized authentication per user
     • Changing or losing either email or phone number won't be an issue

2. Using Phone Number

   • Phone number must be changeable
   • Can have the password as SMS Code
     • Since user logs in once per new phone/SIM
   • If phone number is lost, account is gone

3. Using Email

   • Needs Password
     • Extra burden on user to memorize
   • If email is lost, account is gone
   • Email must be changeable

4. Using Email and phone number

   • No need for Password
   • If Email is lost, phone number can be used for re-authentication
   • If Phone number is lost, Email can be used for re-authentication