The iPad app really serves as an interface for the full cloud-based app on CloudOn's servers, and thus requires an Internet joining to function, but offers what seems to be a remarkably functional implementation of Microsoft Word, Excel, and PowerPoint, all integrated with file storage and syncing through Dropbox.
CloudOn’s WorkSpace allows you to:
Use Microsoft Word, Excel and PowerPoint on your iPad to create or edit documents.
Rename, delete and manage documents with your Dropbox account
Display, edit or create charts, change formatting, spell check, insert comments, into any Word, Excel or PowerPoint files
Track changes while reviewing Word documents
Use pivot tables and insert formulas in Excel workbooks
Display and edit animation or transitions in PowerPoint presentations
Present in full PowerPoint mode (not in PDF)
Open files directly from your iPad email accounts or Dropbox account
Automatically save documents to avoid losing changes