Any feasible solution to read/write simple XLS file on IOS?(I just need plain text)

I found some questions similar to this question was asked but no one provide a decent solution.

I've found two projects on sourceforge (libxls and xlslib) to read/write XLS, but they are under GNU license which I think can not be used in IOS app.

I don't want a full function read/write XLS lib. I just need to write some plain text in several rows and columns.Pretty like just the XLS version of CSV.(CSV is all i need but for some reason i need XLS file format. I can manually read开发者_开发百科/write CSV format because it's really easy to understand. But XLS is way too complicated...XLS format's documentation is like hundreds of pages...I really don't want to deal with like file headers and something like that)

Is there any solution? Or is there any way to easily convert a CSV file to XLS in IOS?