Bart Bonte is back with another puzzle app game.  That's always a cause to celebrate.  blue (game) follows his theme of color games. See links below to my reviews of yellow and red. (I just discovered that black came out last year and I missed it.)
blue (game) has 50 levels. Each level is completely different from each other.  On some levels, I'm not exactly sure what I did to fill the space all up with blue.

I solved all 50 levels in a few hours.  I did consult the hints on maybe 5 levels. https://apps.apple.com/app/blue-game/id1468076893
https://play.google.com/store/apps/details"id=air.com.bartbonte.blue
http://www.bontegames.com/
Other Bart Puzzles:What's Inside the Box"Factory Balls - excellentBoo! - a mini sequel to Factory BallsBlocky XMAS - fun and at times hardYellow (game) 
red (game)Sweet Drmzzz

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