Collaborative smartphone experiments for large audiences with phyphox

We present methods to implement collaborative experimentation with smartphone sensors for larger audiences as typically found at Universities. These are based on the app "phyphox", which is being developed by authors, and encompass simple data collection via web forms well a new network interface allowing collect real-time experiment from an audience on-site or easy submission remote participants. Examples given practical considerations derived first implementations of this method in lecture hall 350 undergraduate students global determine Earth's axial tilt smartphones.