Yes! Apple does not allow you to change the location of your iPhone backup. But, if you are running out of space on your computer's hard drive, you can choose to save your Keepster data to an external drive. This has a small impact on the performance of Keepster, but in a pinch, this can be a useful way to get around space issues.
To change the location of where your Keepster data is stored, use the main 'hamburger' menu and choose Account Management. Then scroll down to the Data Management section. You will see a button to "choose folder ..." and select an alternative location to save your Keepster data. Once you select the new folder you wish to use, click "Save New Settings".
If you already have Keepster data on your computer hard drive, the Keepster app will automatically copy to the new location. Once all the data has been successfully copied, the data from the default location will be removed. This is so if something goes wrong during the process, the original data is not compromised. Please note, if your external drive is not connected to your computer, you will not be able to access your Keepster data.
If you ever want to move your data back to the default location, simple click the "Reset to Default" button and then save settings.