Comment by kukkeliskuu

I have built many projects in hours that we can say would have reasonably taken me a month, to research the technology I did not know beforehand. 30 minutes is often enough to build a first version of the project. For example an audio book listener app, winter swimming iPhone/iWatch app combination, and markdown editor for OS X in Swift.

I have also added complex features in 30 minutes to existing projects, but I don't remember any that themselves would have taken me months though.