Free app for offline reading (only reading ) PDF, WORD, EXCEL, PPT files

Hi

Good day folks

I use an iPhone 5 and an old ipad

I have updated to iOS 6

I need a good Free app for OFFLINE reading ( only reading ) PDF, XL, Word (DOC, DOCX ) and PPT files

Free apps, Only reading and offline ( meaning usable without net connectivity ) and files should be stored on iPhone or ipad

No major synching capabilities needed ... But preferred IF available


Thanks and best regards

Subu