Three methods of connecting to an email server in general from fast to slow include:
- Microsoft Exchange ActiveSync (EAS)
For Gmail, EAS requires a paid Gmail subscription. Google Sync acts as an Exchange server, allowing remote management including remote wipe, app blocking, password policies and more for mobile devices.
Gmail corporate accounts can use Google Sync & Exchange ActiveSync with their non-Android mobile devices:
When clicking the Trash can icon or clicking Delete on a Gmail account connected via Exchange ActiveSync / Google Sync, the email message is either:
- Archived in All Mail
- put into Trash immediately
depending on corporate policies enacted through the Google Admin Console. Corporate retention policies may delete email older than a certain age.
Most people do not use POP3 anymore, since it is more like a one-way connection to the email server. POP3 can be very slow to update with new messages (many minutes). Gmail Settings → POP/IMAP Download allows selecting what happens when a message is accessed via POP.
This is a common connection method for those using non-web, non-Android email connections to Gmail. If you don’t actually have IMAP enabled in Gmail Settings, you can run into perhaps unwanted behavior. This method is typically preferred for personal accounts over POP3 because the connection is bidirectional and many servers allow Push notifications. Push alerts the user to new messages in seconds instead of the 5-15 minute delay in receiving email notifications associated with POP3.
Exchange ActiveSync (EAS) is typically much faster than IMAP. EAS can enforce corporate policy on mobile devices, which leads many organizations to use EAS.