Sprint today introduced a new plan called "iPhone Forever," which grants upgrade eligibility for the newest iPhone to any customer who doesn't have the most current version of Apple's flagship smartphone on their contract. The plan goes into effect today, and the company is opening the data plan to both new and old Sprint users, although the latter must have an upgrade eligible device to start using iPhone Forever.

“We asked ourselves, ‘What could we do that would move our customers forward with the latest and greatest technology every day?’ said Marcelo Claure, Sprint CEO. “We decided: How awesome would it be if anytime customers don’t have the latest iPhone, they are eligible to upgrade, and have it be as simple as handing us your existing iPhone and picking up a new one – all included in your monthly rate.”

iPhone Forever lets customers get an iPhone for $22 a month, with the simple rule that anytime they don't have the latest iPhone on their plan, they are automatically eligible for an upgrade. Sprint is also discounting the service to $15 per month for any customer who trades in an existing smartphone, the catch being that the new phone purchased has to be a 16GB iPhone 6, and the monthly rate will increase back to the normal amount after their next upgrade.

The $15 promotion will last until December 31, 2015, and the company notes that iPhone Forever is available on "any eligible Sprint rate plan." Sprint's announcement today follows a few week's worth of other carriers' detailing the introduction of their own brand new service plans for customers, no doubt all preparing for the next-generation iPhone launch sometime next month.