I Hate Touch Screens

I do think touch screens have some obvious advantages, because they have no fixed layout for UI components, which means the layout can be rearranged for each type of task, and there are no nooks and crannies for dirt to lodge in (try turning your PC keyboard upside down and give it a good shake - it's horrifying what falls out).

However, for a UI that I use regularly, such as my phone, a touch screen offers very little scope for honing speed and precision of use with time, because there's no tactile feedback to indicate whether a key was pressed accurately.

I wish mobile manufacturers would put a transparent mechanical keyboard over the top of the touch display to give the keys feel, while leaving their labels dynamic. The keyboards could also be slid or flipped out of the way when the display is all just for output.