I might just be confused/misreading your comment but you are indeed capable of buying things on android via tap and hold also there's a couple other stores off the top of my head
*SPOILERS BELOW*
there's slime village(albeit not a very useful shop), golden mimic shop which has some pretty nice stuff to help farm gold later on in addition to some stat items, and Bon Bon Bun a candy store. Not to mention all the new stores added with the most recent update.
(Are we counting the shops that sell skills? Cuz that's 3 more if so)