I just tried building a blank app with node-webkit, and the .app file came to around 100MB. It includes the whole Node/Chromium runtime thing. With MacGap it's

I just tried building a blank app with node-webkit, and the .app file came to around 100MB. It includes the whole Node/Chromium runtime thing. With MacGap it's only 1MB for a blank app, apparently. It presumably uses OS X webviews, which don't need to be distributed with it. Obviously node-webkit has a lot more things going for it, like Node/NPM, and cross-platform support. But the size thing does matter. If you are making a basic little utility app, people are going to be suspicious of a very large download size.