Just to get this over with, i'm not laughing at people, i'm laughing with them, and doing so crazily because i am one of them.
Mobiles should have a special button marked with a nut which connects them to a free network to be used by people who feel the need to answer their voices back but are concerned
about their reputations. Unlike [Hirudinea]'s and [Fleasting]'s deas, however, this links all of them together and lets them hear each other, in a huge babble of voices. The result is that they're no longer considered psychotic because they now undeniably do hear voices, the voices drown out the internal rivals and they get to have a conference call with other people with surprising perceptions and views which allow them to audit their own.
However, in order to conform with a likely world view of theirs, this facility is entirely undocumented, allowing the users to build up elaborate theories about what the network actually is, allowing it to mop up a fair amount of their attention, which might otherwise be directed somewhere less helpful.
Oh, and it's a mesh network, not part of the conventional cell network, because then it could be free and local for people who aren't together enough to top up their 'phones or keep up payments on contracts.