First have you tried? Log in to Search the Forum for help! Learn more about using FreeStyler at the FreeStyler WIKI HERE
Learn more about DMX in General at The DMX Wiki HERE
if all else fails and you need a fixture consider the fixture building service HERE
Because android is awesome lol.
In freestyler before connect with iphone right click the connection icon in fs and select disconnect all.
ensure the correct ip is used. you can type ipconfig into cmd prompt and use the local ipv4 value for this.
Also check out the trouble shooting tool in the android section.