What do I need to include if my iPhone App uses some third party code under an opensource licence for example BSD or MIT, before submitting for AppStore approval?
Is it enough if I let original code with it's comments untouched or do I need to include a readme file where I describe that I used "xyz's framekwork under licence abc" or something like that?
There are minor differences depending on which license you use. Most of them are fairly easy to understand, and written in plain, non-lawyer-y English.
The key factors that typically come into play are:
Are you releasing your work as binary only or as source code?
(Which license, of course.)
Have you modified the original or are you using it "out of the box"?
For example, BSD contains the clause:
3. All advertising materials mentioning features or use of this software
must display the following acknowledgement:
This product includes software developed by the <organization>."
Other licenses have other clauses, or parts that say no notice is necessary.
For more info:
http://en.wikipedia.org/wiki/BSD_licenses
http://en.wikipedia.org/wiki/MIT_License
http://en.wikipedia.org/wiki/[name of your license, here]