Yeah, touchscreen makes things way easier in terms of movement (although I've lost some runs trying to lock an egg during a transition and it just hatching).
For the shop thing, I will say that there was only one shop that showed up in the map for the entirety of acts 2 and 3 and I would've had only a little more aura if I went there (admittedly, after spending 750 on the fusion), with the cost being that the extra common items from the forge cause an overflow of items at the bottom which is a minor inconvenience. I agree it's probably better to wait for an act 3 shop in general though.