Cheapest Sprint w/Google Earth

[eenieMINI]

OK what is the cheapest and more important SIMPLEST phone I can get on Sprint that will also do Google Earth? This is for my dad who just uses a regular flip phone but wants Google Earth when he's out and about (he is enthralled with that program). I don't want to confuse him and I don't want to waste my $$ on a bunch of features he'll never use and might scare him away in the first place.

Guy at Bestbuy says Intercept, but I don't necessarily want to buy a current phone, I'm thinking cheap used thing that works.