Do you remember the game Ins and Outs" Color Fence is essentially the same thing: create one loop where some tiles are 'inside' and the rest are 'outside'.

I love the concept, but after you've done a 100 or so, they're all too easy. But still fun.

I had some trouble with Color Fence in terms of the colors. The orange & red squares are too similar.

Even worse: I wasn't able to figure out which colors should be inside and which outside. Look at image #1. In the top right corner are 3 colors. Are they supposed to all be in or all out" I've tried it both ways and neither worked consistently.  I think they've debugged this now.
https://itunes.apple.com/us/app/color-fence/id1263833188"mt=8
http://www.mcpeppergames.com/

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