I'm an iOS developer and one of my apps is a free app that targets Iranian user. The app is free with no ads. Apple asked me to provide an OFAC License to publish the app:
Thank you for providing this information. While we strive to make the App Store available to all developers, Apple must ensure compliance with U.S. sanctions laws before making apps available to customers. In order to proceed, please provide proof of approval from the U.S. Department of Treasury, Office of Foreign Asset Control (OFAC). Apple will accept a copy of the letter confirming release of your app from OFAC restrictions or a specific license from OFAC as proof of approval.
Once we have confirmed you have OFAC approval, you may submit apps for review. For more information on OFAC, you may want to visit the U.S. Department of Treasury’s website or the OFAC FAQ page. When you are ready to apply for OFAC approval, you will need to fill out the OFAC License Application.
I visited their website there but could not find out what kind of application I need, then I asked them via an email and it's their response:
Primary sanctions remain in force. Generally, U.S. persons are prohibited from engaging in direct or indirect commercial transactions with Iran without a general or specific OFAC license. Please see our FAQ page for more information about the status of the Iran Sanctions Regulations. You may apply for a specific transactional license from the OFAC License Application Page. Please be advised that it is necessary to outline details on the exact activity you would like to engage in, and as many details about the payment or financing for it as you can, when applying. Licenses will only be granted if they meet U.S. policy interests and there is no guarantee a license will issued.
Now I'm desperate and have no idea what to do! There are lots of other famous apps which serve Iranian users, all the major messaging apps, social networks, etc.