Although Microsoft's principles for building Office 2013 for Windows 8 (x86) and the Windows RT (ARM) are the same, the Office version for ARM-based devices will have some significant differences.
Screen shots of the two applications (Word 2013 and Word 2013 RT) look very similar because the products are very similar by design:
Differences between the versions are subtle. Office Home & Student 2013 RT includes the vast majority of Office Home & Student 2013 features available on PCs, and the most popular features. Windows RT tablets have special requirements for security, reliability, and battery life, and Microsoft worked to ensure that the RT version is well-suited for the platform. Beyond the differences listed below, Office for Windows RT is fully-featured Office with complete document compatibility.
- Macros, add-ins, and features that rely on ActiveX controls or 3rd party code such as the PowerPoint Slide Library ActiveX control and Flash Video Playback
- Certain legacy features such as playing older media formats in PowerPoint (upgrade to modern formats and they will play) and editing equations written in Equation Editor 3.0, which was used in older versions of Office (viewing works fine)
- Certain email sending features, since Windows RT does not support Outlook or other desktop mail applications (opening a mail app, such as the mail app that comes with Windows RT devices, and inserting your Office content works fine)
- Creating a Data Model in Excel 2013 RT (PivotTables, QueryTables, Pivot Charts work fine)
- Recording narrations in PowerPoint 2013 RT
- Searching embedded audio/video files, recording audio/video notes, and importing from an attached scanner with OneNote 2013 RT (inserting audio/video notes or scanned images from another program works fine)
The Office Home & Student 2013 RT includes tWord, Excel, OneNote, and PowerPoint applications. It will be only available on Windows RT devices and will not be sold standalone. The Windows RT devices available at Windows RT general availability will include preview editions of Word, Excel, PowerPoint, and OneNote. After the final edition of Office Home & Student 2013 RT is released in a user's language, their Windows RT device will be automatically updated with the final edition for free via Windows Update. Microsoft is expected to release these updates starting in early November through January depending on their language.