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This is an office suite that has a word processor, spreadsheet, and presentation app integrated in one interface. It handles most documents created in Microsoft Office, including DOC, DOCX, XLS, XLSX, PDF, PPT, PPTX and TXT file formats.
Office2 HD can access major cloud storage services, including Google Drive, Dropbox, Box.net, Microsoft SkyDrive, Huddle, ShareFile and any WebDAV server. Files can be read and written to these services inside the app.
Of particular note, word processor documents created, spreadsheets, and presentations can be output in PDF format. Documents can also be emailed from within the app.
This is the author's favorite office suite for the iPad.
This office suite from Google is free and is designed for working with Word, Excel, Powerpoint, and PDF documents. It requires a Google account and is tightly integrated with the Google Drive cloud storage.
Quickoffice is not the best office suite in this collection, but it's a solid performer for no cost. The spreadsheet functionality is good and can handle many Excel spreadsheets without problems.
Note that this suite was originally Quickoffice Pro HD until the company was bought by Google. The free Quickoffice app is the newest version released by Google and includes all functionality of the previous version.
This is a full-featured office suite that integrates word processing, spreadsheets, presentations, and PDF file handling. It can work directly with Microsoft Office documents, and is especially good at handling sophisticated documents.
The document editors in DocsToGo are very basic but may be all some professionals need.