BlackBerry Ltd. (NASDAQ:BBRY) announced Tuesday that it would not renew its contract with T-Mobile US Inc. (NYSE:TMUS) following a quarrel over a trade-in promotion that favored Apple’s iPhone.

T-Mobile customers with existing BlackBerry devices will not be affected when the contract ends April 25, and BlackBerry said in a statement that it would help its customers move onto other carriers as well.

“BlackBerry has had a positive relationship with T-Mobile for many years. Regretfully, at this time, our strategies are not complementary and we must act in the best interest of our BlackBerry customers. We hope to work with T-Mobile again in the future when our business strategies are aligned,” said BlackBerry CEO and Executive Chairman John Chen.

The feud began when T-Mobile began a promotion that gave customers $200 worth of credit for trading in a BlackBerry device for the iPhone 5S. Chen at the time said he was “outraged” by T-Mobile’s actions, and the carrier’s CEO John Legere took to Twitter to respond to customers bothered by the promotion.

“BlackBerry users, I’m hearing you loud and clear. Let me work with the team and get back to you,” Legere wrote.

T-Mobile then announced that it was revising the program to give $250 worth of trade-in credit toward a new BlackBerry Z30 or other device from the Canadian manufacturer, and only $200 towards the iPhone 5S. An internal T-Mobile memo said 94 percent of users chose to ditch their BlackBerry in favor of the iPhone 5S, and the carrier took in more than 15 times its usual amount of devices from the Canadian manufacturer.

Chen’s decision reflects the BlackBerry CEO’s more aggressive approach to critics. The Waterloo, Ontario-based manufacturer recently convinced a judge that Typo Products LLC’s keyboard-toting iPhone case probably was infringing on BlackBerry patents.

T-Mobile has also taken a more aggressive stance under Legere, asserting that it is the “Uncarrier” by eliminating the things that customers dislike about their wireless provider. Legere told the International Business Times that T-Mobile was "all about giving our customer choices. Guess BlackBerry doesn't feel the same way."

Follow Reporter Thomas Halleck on Twitter @tommylikey