Name: Your Name (What ever you want)
Email: Your email address is your username
Password: Your 150mail.com account password
Description: 150mail.com
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Hostname: imap.fastmail.com
Username: Your email address is your username
Password: Your 150mail.com account password
Hostname: smtp.fastmail.com
Username: Your email address is your username
Password: Your 150mail.com account password
Click Save Button
Use SSL: Yes
Authentication: Password
Server Port: 993
Use SSL: Yes
Authentication: Password
Server Port: 587
You can login 150mail.com and Signup for 150mail.com new account on your iPhone from here.