Possible Duplicate:
Android Microsoft Office Library (.doc, .docx, .xls, .ppt, etc.)
I have been searching for an API for android to open and view .doc, .ppt, .docx or .pptx.
I'm sure there should be one as there exist applications that can open these file format. I have found apache POI but it uses java awt which is not a part of android.
Even an API to convert these file format to .pdf will be useful.
There isn't a standard API for opening office files in Android. The applications you've found use an internal API for reading the files. They either do this in the device or they upload the file to a server, which is responsible for parsing the file and convert it to a format that is easier read from the Android client.
You can only do so if your phone comes with an application such as Quickoffice, and in those cases, you will be opening it in that application through your application.
How to render PDF in Android
Android Microsoft Office Library (.doc, .docx, .xls, .ppt, etc.)
