The apps have a familiar interface, with the same Ribbon interface and layout. But at the same time, they're not just a port of the regular desktop version. Menus have been optimised for touch; objects can be dragged, rotated or resized with a swipe, and the interface scales properly in both portrait and landscape mode.
There's solid integration with other iOS features. You can use voice dictation to create a document, perhaps, or AirPlay to project your finished presentation.
You get plenty of functionality, too. There are templates, tables, footnotes, filters, charts, transitions and just about everything else you'll need. Everything is very configurable, formatting is preserved so documents look just as you'd expect, and you can save and share your documents via Dropbox, OneDrive, OneDrive for Business and SharePoint.
The core free apps allow you to open or create documents, run basic editing operations or save them.
To use more advanced features, though (Pivot tables in Excel, say) you'll need an Office 365 subscription. If you have one already, no problem; you're covered for all the apps installed on a single tablet in addition to your PC if you have an Office 365 Personal subscription ($6.99 a month) or on up to five different tablets alongside your five PCs or Macs if you have the Office 365 Home sub ($9.99).
What's new in Microsoft Excel for iPad 1.15:
•Stabilization and performance updates.
Other recent improvements are:
•Send with Outlook: send a spreadsheet as an Outlook email attachment and return to Excel.
•Bi-directional and complex script languages: now supports bi-directional text editing and complex script for Arabic, Hebrew, and Thai.
•View protected documents: open and view documents that have access permissions applied to them.
•Easier sharing: invite people to edit a document and grant them permissions, all from within the app.
•Integration with Outlook: edit a spreadsheet attached to an Outlook email message. When you’re done, the updated spreadsheet will be attached to a new email message, ready to send.
• New storage options: open, edit, and save your work to iCloud and other online storage services. (requires iOS 8)
•Excel Add-ins: add functionality to Excel that enhance your spreadsheets and helps increase your productivity. (only on iPad, requires iOS 8.2 or newer)