Hi,
It's not built in Input.touches unfortunatly, so you'll have to do your object detection yourself for now. I haven't done any work on that with Input.touches, my main goal was to make it available to playmaker, and yes, it is quite limiting that you can't really have a convenient way to access picked object or have some system to make it convenient.
Maybe in the future, I could wrap something up.
bye,
Jean