This is a bug with latest version of RaceChrono on phones with Android 8.0 or later. Issue is being investigated and it will be fixed eventually. At least Samsung S7 Active with Android 8.0.0 is affected. For now do this as temporary work-around fix: RaceChrono > Settings > Expert settings > Camera API version > API v1. It will fix the issue for new sessions. If you are affected by this problem, please contact RaceChrono support and send your device details, it will help us to keep track of this issue.