Beepbeepboop
So, it turns out that while my phone is quite good at being a camera, an MP3 player, a text reader and various other uses - it's not actually very good at being a phone. I was in a rather important phone call when I heard a 'beepbeepboop' chime in my ear, the call cut off, and the phone's screen went white. It had locked up solid - I had to remove the battery to get it to reboot. Hmph.