Help with Mobipocket on java mobile phone...

I just bought a new LG900g phone and no matter what I do I just CANT get the Mobipocket app to work:(
It keeps telling me there are no books in my library but I know they are in there, I put them in the ebook folder in my phone and it still doesn't detect them, are they in the wrong format? What format do they need to be in in order for them to be recognized?

Mobipocket has always been my reader of and its annoying me that I can't get it to work on my phone. I read constantly and having to convert all my books to JAR files would take forever! I would much rather use Mobi. Does anybody else know of any working ebook readers? Ive tried every one I can find but most are either to complicated for me or they won't work...