Make Filmroom system checks part of your pregame ritual. Get the Filmroom Pregame Checklist.
Set up as high as (safely) possible in the stadium. Above the press box is ideal.
No press box or stands? Consider shooting from one of the endzones.
Your best video playback experience will be on iOS devices, but if you're on a budget consider using an inexpensive Android device for recording. You won't notice difference in video quality or speed.
Use a tripod mount and lens kit. Filmroom includes a digital zoom but a 2x telephoto lens will give your mobile device a nice optical boost.
Pick a sturdy tripod with a smooth pan head.
Choose someone dependable to handle recording, and emphasize the importance of stopping the recording between plays.