Maximum PC: Wireless carriers are currently engaged in a high stakes game of one-upmanship as they each try to add more subscribers by offering increasingly tantalizing offers. Sprint's strategy was literally called "One Up," the name it gave to an early upgrade program it introduced just four months ago. One Up customers could purchase an eligible smartphone with no down payment (depending on the device) and spread out the full retail cost over 24 monthly installment payments. In exchange, One Up customers could upgrade their handset every 12 months and start the process anew. Now the program is no more.