Have used phone on playa for at least 5 years. Reliably. AT&T iPhones 3 & 4.
5W amplifier and a well placed high-gain antena on the roof of the truck does the trick.
It will set you back a few hundred for the gittup but at least it works the remaining 51 weeks as well.
For all I know this may have worked out there longer, but 5 years ago is when I tried it for the first time.
Fuck yer day.
