Recent reviews by nml

Pros:
Fun concept
Fun for co-op
One particular puzzle mechanic I found particularly deep and interesting (the "make a plus-shaped wall" mechanic)
Puzzles are a good difficulty - if you've played enough puzzle games it's pretty obvious what the general idea of a puzzle is, and it feels like you're making progress through each puzzle as you go.
I didn't try it, but I can see how it might be entertaining with a bit of antagonism as "soft" PvP, especially in a party setting

Cons:
A little obtuse

• Means of getting to the next world was more confusing than it needed to be
  
• I thought a puzzle was impossible until I accidentally found the world mechanic by spamming directions

Lacking in options/settings

Overall a fun little game that's worth the price of admission.

1 dollar for 59 minutes of fun. Pretty good deal.

Most of the puzzles are fairly simple, and most are somewhat easily brute forced if you don't feel like using your brain. And honestly, this is a pretty good game to play if you just want to chill out, because the ambient music is very soothing.

There were 7 or 8 different mechanics that the developers toyed with for varying amounts of time, eventually using most of them in combination. The "15-puzzle" sections I found a little tedious, but it did add something to a couple puzzles.

I tend to prefer more difficult puzzle games (HexCells, The Witness, etc) but this is easily worth the small investment for any fan of the genre.