See the requirements here: <http://www.irs.gov/Individuals/International-Taxpayers/Foreign-Earned-Income-Exclusion---Requirements>

I'm currently living in Costa Rica. Assuming I live out of the US at least 330 days a year, can I qualify for the foreign earned income exclusion? I have a single member LLC currently based in the US (although I could change that). Assume my income comes completely as 1099 from other businesses (clients), and/or from Apples App Store. 

Do I qualify? Is there something I can change so I do?

I was advised by my accountant before leaving that I could get out of state income tax but not federal. However, my friend has succesfully used the exclusion on income earned from ads on his websites, was told by his accountant that it was correct, and was not corrected by the IRS. Who is right?