I have noticed that I can never answer the phone quick enough on my Android phone with the app, it rings once or twice so I have to be very quick.
Today when I was talking to someone they said that it was ringing for ages before they hung up but I only got two rings on my mobile (no idea how many technical rings are described by 'ages', but I would expect more than 1 or 2).

Anybody else use this app and have it working fine?