Sprint is reportedly preparing to launch an early upgrade program for smartphones in the wake of similar offerings from AT&T, T-Mobile and Verizon. Known as Sprint One Up, the glorified handset rental service is expected to debut on September 20. Better late than never, right?

One Up is said to allow customers select a smartphone with no money down and spread the cost of the device over 24 monthly payments. For example, a handset that sells for $649.99 would be around $27 each month on top of the monthly rate plan. After one year, the customer can elect to trade in the original device and start making payments on a new phone.

Sprint will allow existing customers that have been on contract for at least a year to sign up for One UP although they will need to trade in their current phone unless they are eligible for a full upgrade. Prepaid customers aren't eligible for the program.

Sprint's plan seems more in line with T-Mobile's Jump plan in that a break is given in exchange for the monthly installment plan. Programs from AT&T and Verizon continue to charge the same monthly rate plan on top of having to also pay extra for a new device.

Of course, once you do the math, you'll quickly realize that all of these early upgrade plans are a complete sham. Assuming you take the upgrade as often as possible (either once or twice a year), you're basically renting a phone at a premium and will never have anything to show for it (a phone you own).