HTC has prommised to release tools to unlock the bootloader of Android devices. HTC are rolling out this service for one device at a time. HTC Sensation is now unlockable
HTC Sensation European version is the first smartphone to be listed as a supported device on the HTC developer site. This meanst that owners of HTC Sensation can find step-by-step instruction on how to unlock the bootloader of their Smartphone.
So why would anyone need to unlock the bootloader? The bootloader is a tiny program that desides which application must run in the startup (boot) process. By unlocking the bootloader the user can customize software on the Android device.
This is all good right? Yes the user is given more control over the device, but something can go wrong and then you could be in trouble. HTC unlocking process requires you to send unique device information to HTC to be able to unlock the device. HTC therefore have a list of devices where the owner have tried to unlock its device. This is important, because by unlocking the device the user have agreed to the disclaimer that states a change in warranty status such that if the user render the device unusable he/she is responsible for the recovery.
Unlocking a device requires some knowledge of installing the free Android SDK application suite, connect the phone to a PC and view the device indentifier token. This token is sent to the HTC web site and the user receives a unlock key by email which he later use to unlock the device.
The next two devices up for unlocking is HTC Sensation 4G (T-Mobile USA) and HTC EVO 3D (Sprint USA).
Read the unlock bootloader instructions over at the HTC Dev web site