That's the best way to politely tell someone don't turn on the mobile phone...

When being rudely interrupted by a cell phone during his concert, a violinist surprised the audience by playing along with the ringtone (Nokia). It's always happen in live performance even in Hong Kong, China, Germany, France. It's interrupt the performers and audience. The main point is Lukas Kmit use a polite way to pass a message to the audience PLEASE turn off your mobile phone. Anyway, we need to learn how to respect performers because they work very hard, it's a big interruption.