I downloaded this on my iPad a few days ago. There is a tone generator, wiring diagrams, enclosure volume and simple box building program. It does not allow for Round portas, however there is a section where you can calculate round port tuning and it will give you desired length. You have to know a little about enclosure design though in order to get it to work for you, you can NOT be a noob to enclosure design. All in all, it's a good app for the Apple market, one of the best I've seen so far. Well worth the $.99 in my opinion. Any questions about specifics of what the app includes,PM me or whatever and I'll let you know if it has what you're looking for