It's important to synchronize your camera(s) with a device that has a concept of what the actual date time is. All electronic devices have temporal "drift" while they are turned off and GoPros are notoriously bad at maintaining the time even if they are off for <1 minute. However, your computer and Android devices connect to the internet to synchronize their time. Page 2 & 3 in this manual explains the importance of synchronization a little more: https://s3-us-west-2.amazonaws.com/agribotix-manuals/FarmLens+Uploader+Instructions.pdf
However, to synchronize your GoPro with an Android device (which should be done before each and every flight that you do).
- Go to your GoPro app on your Android device and click "Connect your Camera".
- If you haven't added your camera, click the "Plus" at the top right to connect the camera to the Android device and follow the instructions. Otherwise turn on your GoPro's Wifi and connect to it, and click it from the list.
- You should be taken to live feed of the camera.
- Click the wrench icon on the Android device while on the live feed and scroll to the "Setup" section of the list of settings.
- Now click "Set Date and Time". It should pop-up briefly with a window that has a spiral loader, then shows a check mark and promptly closes.