Not just owning two phones simultaneously - using them simultaneously

That sounds extreme even for me, but apparently it's becoming more common. Phones are

Optimized for one-handed operation. It means we can rather easily learn to use two phones in two hands. This gives the mobile a powerful advantage over other digital mass media, whether the PC or Playstation or Digital TV - we tend to only consume one of those at a time. But we can rather easily consume two distinct mobile phone based services - on two separate phones - from two competing networks even - simultaneously. Or, we can consume mobile services while we are supposedly paying attention to the other older media such as our broadband internet (sixth mass media) or TV (fifth mass media) or a video game (ie recordings, the second mass media channel).