At least you can get as far as unlocking the bootloader on that device :P on the Samsung Galaxy Tab 4, it's impossible to unlock it. At least you can get TWRP onto it.I never really use my phone as an alarm clock, that's what actual alarm clocks are designed for.
And speaking of the HTC Sensation, I'm in the process of trying to install CyanogenMod 11 on a friend's phone to bring it somewhat up to date. But damn they make those phones hard to mod. You first have to unlock the bootloader, then do a temporary physical modification to allow Recovery to write to the /boot partition of the device.