I tried a lot of solitaire apps before settling on Solebon. It is by far the easiest to see and to use. One quick tap and it guesses (mostly right :) where you want the cards to go. Understands how to use feee cells.
Don't bother with the "winning deals" though. Too easy. Haven't a random deal yet that I couldn't win.
Small defect:
1. Needs a Redo button as well as Undo.
2. If you have 2 empty places in the tableau and 1 free cell and you're moving 4 cards, it doesn't know how to do that. You have to tell it to move 2 cards to one space and then the last 2 to the other space and then move the first 2 onto the last 2.
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