[turingbook]

According to the story by Pandodaily [1], "It’s a native OSX app, but it was built inside a customized version of Google’s Chrome browser. " I guess that it will be relatively easy to target Windows and Linux if they want.

[1] http://pandodaily.com/2013/10/17/macaw-a-kickstarter-funded-...

[dubcanada]

I believe it is using CEF, so porting it to either OS's (including Linux) will be pretty easy.