Dash is one of those Mac apps you didn't realize you absolutely needed until you have it (like Bartender or FlyCut or Divvy). That said, buying it again for iOS isn't appealing.
Is the 'buying' not appealing, or is using Dash on iOS not appealing? If you don't think you would look up API much on an iOS device, fair enough. For me, being able to use an iPad as my go-to documentation viewer is tremendously appealing. This is a professional tool, that I use daily (on OS X), and having it on iOS will make my life better.
I don't even have the app, but I really don't like this argument if it has to do with "buying it again". It's not easy writing an application for iOS even if you have one for MAC. They are going to have different feature sets, and now, parallel maintenance times. Why shouldn't he charge for it? (It's also half the price)
