I'd say it'd be pretty easy to get lost in there...Sometimes a mindless escape into a gadget is the only sanity break we can get. Scroll around, load a new app, check the weather next week -- then once more unto the breach.
Yes, I think it's escapism - which is harmless in small doses - but the trouble with escapism is that, if it is prolonged, then it can become too much of a good thing, whereupon such a putatively relaxing "mindless escape" can become a real time bandit where one can spend a great deal of one's cognitive surplus (and experience of life) in playing with (say) a smartphone, or watching TV, or something.
Having discovered that to be the case for me with an HP Palm some time back, I had to try to be more self-disciplined. I would have no desire to succumb to a new temptation manifested in the form of a smartphone, unless I have a real and defined business use for it.
I guess there's a dividing line between "play" (where one can risk learning and then practicing something) and "mindless escape".
Quite different to daydreaming, which seems to be an entirely natural and potentially useful way for the mind to think and reflect at random/whim, and to sometimes come up with new ideas.