Only for 10 more hours, but Glass Masquerade is 80% off as the star deal on Fanatical ($1 US). Appears to be 50% off on Steam for the weekend if you miss the star deal.
http://store.steampowered.com/app/511470/Glass_Masquerade/
Really beautiful art, soothing jigsaw game. Intuitive controls.
Puzzles have fewer pieces than, say, the Pixel Puzzles series, but still present some challenge albeit fast-paced by jigsaw standards with a medium difficulty puzzle taking 5-7 min for me.
Is actually quite enjoyable to play, whereas I found PP to be a bit clunk, esp. at higher piece counts due to the scale, lack of any save function, and the sheer mass of pieces floating around a board.
For any jigsaw fan I would say this is almost certainly my favorite digital puzzler so far. Will definitely replay with my child as well at some point.