Boxer supports push for Gmail, Google Apps, Outlook.com, and Hotmail accounts only. Boxer also supports background sync and polling for new messages for all account types.
Unlike push, polling does not notify you immediately when you receive a new message. Instead, it checks for new messages as often as Apple will allow, and alerts you as frequently as your settings allow. The frequency with which it checks for new messages is determined by Apple; the more you use an app, the more often it will check for new messages.
To turn on polling:
1. Open up your iPhone/iPad settings app.
2. Select "General."
3. Select "Background App Refresh."
4.Turn the setting for Boxer to "On."
If you are just getting started with Boxer and are not receiving immediate notifications for your IMAP / Exchange / iCloud account, you should find that the more you use Boxer, the more notifications you will begin to receive, and at a more regular frequency.
We do plan to add in push support for all account types in the future. If this is something you'd like to see, you can vote for it here: http://support.getboxer.com/forums/236855-feature-requests/suggestions/5511560-push-email-support-for-all