Encryption in your iPhone application? Get ready for paperwork.

ITAR (munitions) compliance is not a particularly new aspect of software export; if you were exporting encryption, you need(ed) to work within the rules.

In my experience, ITAR compliance has gotten easier, too.

Using existing and available encryption libraries (and at settings below military-grade) is usually the easier approach. This rather than rolling and then reviewing your own encryption. Certainly for ease of export compliance, but also because rolling your own encryption code is one of those design and programming tasks that is far harder than it looks, if you really want to get that code "right".

There are certainly other considerations around exportation and with working internationally.

If you're not sure, check with a legal services firm; with the folks that know the details of complying with export and import requirements, and with individuals and businesses and countries you can (and cannot) work with internationally.

http://www.pmddtc.state.gov/regulations_laws/itar.html