Name: Your Name (What ever you want)
Email: Your email address is your username
Password: Your bestmail.us account password
Description: bestmail.us
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Hostname: imap.fastmail.com
Username: Your email address is your username
Password: Your bestmail.us account password
Hostname: smtp.fastmail.com
Username: Your email address is your username
Password: Your bestmail.us account password
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Use SSL: Yes
Authentication: Password
Server Port: 993
Use SSL: Yes
Authentication: Password
Server Port: 587
You can login bestmail.us and Signup for bestmail.us new account on your iPhone from here.