MailDroid is an Exchange/POP3/IMAP Idle Push mail client written from the ground up and not based on the stock mail client.
This is the Pro version of MailDroid and contains NO ads. The pro version does contain some extra features that are not available in the ad version.
*ADDITIONAL FEATURES IN PRO*
1. Up/Down arrow in email to move to next or previous emails
2. Volume Hardware buttons to move to next or previous emails
3. Ability to set where to go after deleting an email (next/previous or back to inbox)
4. Two Widgets
5. Switch between 3 icons when adding the counter widget
6. Reply, Reply All, Forward, Delete and Archive are available on expandable notifications (up to 3 choices)
7. More will be coming…