Apple (AAPL 1.27%) and T-Mobile recently announced an agreement that will likely allow T-Mobile to begin selling Apple's iPhone. In this video, Motley Fool senior technology analyst Eric Bleeker takes a look at what this deal's impact on Apple will be.  With approximately 34 million T-Mobile subscribers, plus an additional 9 million upon closing of T-Mobile's pending acquisition of MetroPCS Communications (TMUS 0.57%)), Eric expects that this deal will result in the sale of approximately 1 million additional iPhones per quarter, based on the performance of Sprint (S).  This translates into an increase of around 3% in the quarterly sales of iPhones, which Eric characterizes as good news, but certainly not a game changer.

The big question on Apple investors' minds is which carrier will be next to sell the iPhone. Many investors expect an agreement with China Mobile (CHL) in the next couple of months. Like the T-Mobile deal, an agreement with China Mobile would certainly boost iPhone sales. However, Eric urges investors to keep the scale of the potential upside from these deals in perspective, given the iPhone's large existing base.