Repurpose your old phone as a dashcam with Veritas. Automatically start recording when your car starts and save clips by voice command or with the automatic collision detection.
Free Version: https://play.google.com/store/apps/details?id=com.KillerPokeGames.VeritasFreeDashCamForAndroid

Features:
- Pick front or back camera
- Customize recording size and quality
- Voice commands to start, stop, and save video recordings
- Automatic recording start and stop through usb charger power
- Minimum sharpness check to prevent auto focusing on windshield
- Auto save on collision
- Minimum free space, and maximum video space options
- Keep screen on and bright while recording