It's not The Witness, but it is a puzzler by a talented indie developer. 1Button, known for games like Nekosan [Free], Mr Jump [Free], have created Trilogic [$1.99] as a followup to Bicolor [$0.99], their puzzler from 2014. Naturally, the big new element in this game" Instead of having two colors in a puzzle to contend with, now there are three different elements in a puzzle to play with. With a bit of Minesweeper influence, icons will show how many of that element you can drag from that spot into the board. The elements play a role, too: leaf drinks water, fire burns leaf, and water puts out fire. This order is key to solving the puzzles.
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This is another neat little puzzler from 1Button that is easy to play, but will quickly prove to be quite challenging. It's $1.99, and has 180 levels, and the only IAP is for skipping levels if you get stuck. 1Button has a great track record, and the idea seems quite clever from what I've played, so give it a shot if it interests you.