If you already bought PS Touch, the app should be available to you indefinitely under the electronic marketplace account you bought it under. (At least I still have it under my Google Play account.) It's just that Adobe discontinued its development and won't be for sale anymore for anyone that hasn't bought it.
The stickler here is that whenever we all upgrade to the latest and greatest mobile OS, there's the possibility that PS Touch won't work on it.
The first versions of the newer mobile apps are available for phones right now. The next updates should open them up to tablets. People have successfully sideloaded the APKs on tablets.
I have some questions of my own that I hope will be addressed whenever I get my hands on them since I use a tablet as well. I have a smartphone but the only thing I use it for is for emergencies and my shopping list. I keep badgering them to hurry up (nicely, of course) but the wheels of Adobe development turn slowly, as it were. lol
What I do know is that the forthcoming Project Rigel looks more or less like a version of Camera Raw with some warping. (That's good.) Photoshop Mix has some editing features but with only 2 layers maximum. (That's bad for us creative compositors.) The new mobile apps are free. (That's good.) But they might just end up being an extension of their desktop counterparts. (That's both good and bad; good that we modularly (is that a word?) connect to their desktop counterparts to complete a project; bad that we can't use a mobile solution to create a final product like we could with PS Touch.)
my biggest issue with Adobe discontinuing ps touch isn't even that they're not making an equivalent alternative, it's that there is no alternative at all.
with almost every type of app you can just switch to a competitor, but there is no other full image editor out there unless you count a Linux VM with gimp pre-installed.