You are not allowed to speak in your mobile phone while riding the Stockholm subway trains. A strange rule possibly, since the difference between speaking to someone in a phone and speaking to one and other in the tram isn’t too distant to each other. Does it bother you when people are communicating? In general, no, you would probably say. Speaking out loud about private matters in a phone should be as annoying as talking about it face to face.
And when a face making looney for a man is playing his electric guitar, with ear phones luckily, next to you I would rather have him speaking in a phone. Maybe he’s just very addicted to playing guitar or maybe he likes doing it in front of others. Ok, so the every day travelling can be boring, but not that boring! And playing guitar is a lot more fun than reading crappy newspapers, even if they are free, but if your so addicted that you have to play it while getting a public transport you should be a bit worried…