Samsung smartphones have always had plenty of support from custom ROMs like CyanogenMod, allowing owners who hate the TouchWiz user interface to replace it with something a little more like barebones Android. But Galaxy S4 owners on AT&T may not have that luxury.

According to CyanogenMod founder Steve Kondik, the AT&T Galaxy S4 comes with a locked bootloader, which could rule out the possibility of flashing custom ROMs. Kondik has advised those who might be interested in this kind of thing to look for another carrier.

“Yep, it’s confirmed. The AT&T S4 authenticates the recovery and boot images before executing them,” Kondik wrote in a post on Google+. “I can’t see what AT&T has to possibly gain from this.”

Kondik goes on to note that locking the bootloader doesn’t prevent unauthorized tethering, and that AT&T clearly didn’t do this for exclusivity because the Galaxy S4 is already available on every other carrier in the U.S. He also says that Samsung has always been “developer-friendly” — Kondik worked for Samsung for a while — and that it’s likely “their hand was forced.”

So what does this really mean for end users? Well, it’s highly unlikely you’ll see custom ROMs for the Galaxy S4, so if you buy one, prepare to stick to the software that Samsung provides you. Trying to hack it could just lead to nasty problems.

“The only outcome I see here is stacks of bricked devices being sent back for warranty replacement due to the ease of causing a permanent boot failure, especially since the device is trivially rootable,” Kondik writes.

There is a chance, however, that developers work out how to unlock the bootloader, opening the door for custom ROMs. But if you purchase the Galaxy S4 in the hope that this will happen, then you could end up very disappointed in the coming months when you’re stuck with Samsung’s software and an unlock still isn’t available.

With that being the case, Kondik advises users who want to install custom ROMs to look at other carriers if they want the Galaxy S4.

“I would not recommend buying this device on AT&T if you want to run CyanogenMod or another custom ROM, or if you are a developer and need to work with or debug the lower layers,” he said.

• SourceGoogle+