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.