Install it and forget about it
A lightweight Status Bar App that works in background, BackUp Gmail connects automatically with your accounts (yes, it is multi-account) and backs up any new message.
Plain text data
You can access your data whenever and wherever you want. All emails are in plain text (.eml format, with attachments) and the relationships are stored in a SQLite DB.
Restore in a simple way
To restore select an account and provide the new credentials. If something goes wrong you can always resume the old restore in progress.
Set Folder and Schedule
You can personalize how the backup is performed and set-up your destination folder as you wish. You decide if you want an hourly or daily backup of your account, and set the times yourself.