I think you're likely to enjoy creating iPhone applications using Tersus. Since iPhone support is quite new for us, you are likely to hit some rough edges, but we'll be here to assist you.
The presentation layer of Tersus applications (including native iPhone application) is based on HTML. This is a limitation if you want to do something that is really heavy on graphics and animation, but for normal applications it's a big plus. You get all of the flexibility of HTML and CSS (including the ability to use new CSS effects like transforms and animations). To fully benefit from this flexibilty, it's best if you know (or learn) CSS.
We're not of aware of a Tersus application being already available on the AppStore, but based on the experience of PhoneGap, which uses a similar approach, we don't expect a problem.
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