GuestDJ turns every phone into a song request line. Guests scan a QR code, choose a song, and send it to the DJ, no app, no signup. The DJ stays in control, approve, reject, reorder, or pause anytime. SingAlong Mode shows live synced lyrics on TVs, projectors, and every phone, line by line in time. Five display themes, genre filtering, drag and drop queue. Works on any device.