T-Mobile announced last month that they would be introducing an unlimited 4G data plan across the country to consumers tired of paying for tiered data from the big guys. It was supposed to be available on September 5 and T-Mobile has stayed true to their word.

T-Mobile announced today that their Unlimited Nationwide 4G data plan is now available to customers at their stores or online. It should be a big boost to T-Mobile’s business after consumers have become increasingly fed up with Verizon and AT&T only increasing the prices of their plans.

“Since our inception, we’ve always strived to shake up the industry with plans, network capabilities, and innovative products and services for our customers,” said Brad Duea, senior vice president, product management, T-Mobile USA. “Today’s release of our Unlimited Nationwide 4G Data plan continues our tradition of bold moves that enhance the customer experience and change the way wireless is done.”

To convince people to make the switch, T-Mobile is offering a free (after rebate) HTC One S to all who sign a two-year contract. Offering a free HTC One S is a pretty tempting offer when you consider it’s one of the best Android handsets on the market. It will also be getting an upgrade to Jelly Bean later this year.

Even with the offer of the free HTC One S, it doesn’t excuse the elephant in the room – no iPhone 5. The iPhone 4 and 4S were just recently made compatible with T-Mobile’s network, but that requires customers buy an unlocked iPhone at full price. Not being able to offer a subsidized iPhone 5 alongside their unlimited 4G plan might hurt T-Mobile in the long run.

Regardless, T-Mobile has become a good guy of sorts among mobile carriers. Offering an unlimited 4G data plan only further cements that image. It still might not be enough to convince people to switch over from carriers that do offer the iPhone and will be selling the iPhone 5 day one.