It not only helps you to keep a backup of your application data in the cloud so that you can always restore it, but it also provides a neat way to transfer the latest game saves from your iPhone to an iPad or iPod Touch.
The official Dropbox app (iTunes link) currently only allows users to upload the photo library to their Dropbox account as that is what is possible using the official APIs.
Here’s a brief description of the app from Cydia:
Backup iOS application save data to your Dropbox account, and restore to another device! Great for synching your Angry Birds save from your iPhone to your iPad, or ensuring that you never lose any data.
It’s quite easy to use, when you launch the app, it gives you the list of apps you’ve installed and you have to select the app, you would like to create a backup for. Once the application data is backed up, you should be able to see a zip file for that app in the “DataDepositApp” folder created in your Dropbox account.
If you want to transfer the application data from your iPhone to an iPad or iPod Touch then install the app from Cydia on that device. When you launch the app and select Restore from Dropbox. You’ll see the list of apps that can be restored from Dropbox. Tap on the app to download the application data from Dropbox and restore it.
Please remember to close the app if it is running in the background (via the multitasking bar) before taking a backup to avoid any issues. Though the backup process worked for the few apps we tried, it might be a good idea to double check your Dropbox account to confirm that the application data has been successfully backed up.
DataDeposit is available for free on Cydia. If you don’t have a Dropbox, then you can create a free account (using the app or going to Dropbox’s website), which comes with 2GB storage that should be ideally be sufficient for this purpose.
If you give it a shot then let us know how it goes in the comments.