gmail backup application is very small in size.

[Jasmine123]

HI guys,

It’s capable to backs up multiple Gmail accounts to you backup disk every hour. This is a very helpful application to save your Gmail data quickly and automatically. This application is very small in size, but extremely fastgmail backup for Mac  works in silent mode in background. You don’t need to remember it after installation.

https://itunes.apple.com/us/app/backup-gmail/id492622242?mt=12