For phone app login

Please download BlueMail from playstore

Android https://play.google.com/store/apps/details?id=me.bluemail.mail

IOS: https://apps.apple.com/us/app/blue-mail-email-mailbox/

Setup steps

Step 1: choose add other account

Step 2: choose other email

Step 3: fill in your email address and password

Step 4: its last step, just fill in your name for you own record.