If you have an Android device and have communication issues using the Image Sync app, please follow these steps,
- Uninstall the Image Sync software
- Reinstall it again.
- Remove the paired GR camera from the smartphone bluetooth setting.
- Delete the WiFi connection with the camera on the smartphone WiFi setting.
- Disable power saving of the smartphone
- Release pairing device on the camera menu.
- Connect again from the start.
For additional information refer to the "Cautions of Bluetooth connections"