After you have installed the app and started it for the first time you will be asked a question as shown above press yes as are updating your app and you have backup select the folder and the backup will be accessed and extracted then the app will close itself. Start it again and use the app.
If you have installed the app on some other app and you want to move or migrate data from that device press Other device.
Cross device restoration
Cross device data receiving page
After Pressing Other device button you will be directed to this page it will have a security pin. Enter this pin on the device you are going to send data from both device should be on same network and device can be any device (Android or windows) on which this app can be installed and used. For more info on how to send data click on the link below