Export message as .eml
Mail.app for OS X does this quite elegantly: Simply drag a message to (for example) the Desktop and you get a nice .eml file for sharing (via sneakernet) or backup purposes. Sadly, it doesn't seem like Mail for iOS can do this, so it would be great if Boxer could.
(Perhaps this can be implemented through first generating the .eml after the user presses an 'Export' button, then popping up an 'Open In...' menu so the generated .eml file can then be stored and opened in other apps such as GoodReader).
For this you can actually try using "Cloudbacko pro" for taking backup. This software not only gives backup but helps in recovery also. I am basically using this software from long time and really satisfied using this software. If you want you can actually use many software that are available in the market but i will only suggest you to take backup and recovery from this software only. Thanks.