From the creators of iOSC, an iPhone application that can communicate with other compatible hardware and software nodes on your network, come two new sound application: Powon and NNN Mono. Considering Powon is a free app, this makes it a must download. If you are looking for creative synthesiser app, NNN Mono definitely deserves a closer look. There are plenty of videos on the site (see some below), that should give you a good overview of features the app includes. Here is some more info on each app.