Office Mobile for Office 365 is an Office companion app which allows you to access, view and edit your Word, Excel and PowerPoint documents on the iPhone.
As you might guess from the name, you'll need an Office 365 subscription to use the app. But once you've got that, Office Mobile allows you to access Office documents stored on SkyDrive, SkyDrive Pro, or SharePoint. It can also be used to view and edit documents which arrive as email attachments. And, conveniently, documents you've recently viewed on your computer will automatically be available from your phone's Recent Documents panel.
You can also create Word and Excel documents from scratch, and carry out some basic PowerPoint revisions (move and hide slides, edit your speaker notes). The program interfaces have been optimised for the smaller screen size, to make this as simple as possible.
When you're on the move then it's not always possible to maintain a reliable internet connection, of course, but that's not an issue here. Office Mobile for Office 365 allows you to edit documents offline, and will save any changes when you next connect to the network.
And once you've created your document, edited it or just added a few comments to someone else's work, you can simply despatch it via email, or save the file directly to SkyDrive or SharePoint.