Company planning to use my personal smartphone for location tracking. Is it legal?

My company plans to use Drawinbox software for HR purposes, and they are forcing people to install drawinbox mobile app, so when employee comes to the office he need to use this app to scan his face, the app is checking your location and register the time when you come to the office. Same for lunch and checkout after work. For me it seems too much especially taking to the account that I have to install this app on my personal mobile phone. + is it even legal in Germany to trace employees location? 😨 What should I do …