Loyal Blog Follower Joel from Germany alerted me about Ichi-Ni. It's another topology puzzle app game. The object is to start at one of the brownish squares, traverse over all of the green squares once, and end at the other brownish square.
  We've seen this type too many times to count.
What's different"
1. Some of the green squares have to be crossed 2 or even 3 times. Actually, we've seen this before.
2. Purple wormholes. We've seen this too.
3. Yellow squares. When passing over a yellow square, it will turn green and move to a new spot. This we've never seen before! 4. Starting at level 57, some green squares turn black temporarily, so you have to time your path.
5. Starting at level 65, the stripped green squares travel along an invisible track.

I thought level 55 was pretty tough. After about 10 attempts, I had my 'aha' moment.
https://itunes.apple.com/de/app/ichi-ni/id1025335938"mt=8

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