Keepsafe does not actually have a "log out" option. In order to log out of your Keepsafe account, you must uninstall your Keepsafe app.
However, this is NOT recommended - any unsynced content will be permanently lost in the process.
If you still intend to do so, please make sure that all of your items are synced with the Private Cloud before uninstalling the app. Only the backed up content will be restored when you log back into your Keepsafe account.
If you're using an Android device and wish to log into a different account, please follow these instructions