Using Aquamail to read work emails is a lifesaver. This is even after tightened up security to require a VPN.
Aquamail still gets the job done. I can sync and read my mail on the phone. The setup is super simple. Just enter my email address and it is done. I think it works by using Outlook Web Access. This is a pure email client. For calendar functions, open calendar and you can send invites there!
The Smart folder feature is really useful to filter only unread mails. The downside is that it is too efficient. If you want to swipe back to check on the previous read email, it would have been removed from the Smart folder! I find that reading the subjects in the summary page of the Smart Folder a better fit. I can take action, such as delete or mark read. Emails that I want to take action, I can leave it as unread.
You can’t attach an email in another email. I think Aquamail works by scrapping off Outlook Web Access, this appears to be a common limiting factor in most web-based email.
It is an Android-only app and free!. Unlocking enables you to create signatures.