And now he says he also feels burned by how T-Mobile responded to his injury.
The incident all began when Jaime Walls woke up Tuesday morning with a burning feeling.
"I went to roll over, and I got such a sharp pain in my back," he says. "I see my phone. I went to pick it up and move it. And as I grabbed it, I had to let go because it was so hot that I couldn't hold it in my hand."
At the time, he was more concerned that the phone, HTC's myTouch Slide, didn't work. Twenty minutes later, he was at the Issaquah T-Mobile store.
"And they said, 'The phone is fried,'" he relates. "Oh, it smelt like burnt plastic - bad."
It was insured, so T-Mobile replaced it with the same phone; he had no other choice. But as he was returning home, the pain came back.
"By the time I got home, my wife looked at my back, and she said, 'You've got a huge burn on your back.'
In fact, the burn was blistering. So the couple took pictures.
"I can't believe a cell phone can get so hot that it would injure someone like that, and I can't believe T-Mobile doesn't care," says Emma Walls.
Walls says T-Mobile told him to write a letter of complaint to the home office.
"Well, I live 20 miles from the home office. I'm not writing a letter, I'm driving down there," he says.
And he did, to T-Mobile's world headquarters in Factoria to show them his burn.
"It was just denial, denial, denial," he says. "They wouldn't let me pass security. They were just angry that I was there."
Instances of cell phones exploding, catching fire and burning people have happened, but the cases are rare.
KOMO News couldn't find any other case involving HTC's myTouch Slide.
T-Mobile and HTC chose not to answer any of our questions, and issued this statement instead:
"We are unaware of any similar issues regarding this device. T-Mobile and HTC are working to investigate this matter, and we are in touch with Mr. Walls directly. We take the quality and safety of the products we sell very seriously."
Emma Walls says, "And when he goes into complain, and they say we've never heard about it before, it doesn't really matter. That's not OK, 'cause it could have been worse. If they don't get on to it now, it will be worse."
The HTC myTouch Slide is fairly new. T-Mobile started selling it on June 2, and Jaime Walls bought his first phone about two weeks ago.
He said he wants people to know what happened to him - but he has no plans to sue T-Mobile over what happened to him.