After more than a year of rumors, Microsoft today finally released a version of its Office suite for the iPhone.

The app, available for subscribers of Redmond's Web-based Office 365, includes iPhone versions of Word, Excel, and PowerPoint, which allow you to create, edit, and update all of your documents and sync them with Microsoft's SkyDrive cloud storage service.

However, for long-time Office users, the arrival of the app on the iPhone will likely come as bittersweet news given the stipulations surrounding its availability. Any iPhone user can download the app, but without a subscription to Office 365, you can't actually use any of its programs. Office 365 Home Premium subscriptions cost $99.99 per year and the Small Business Premium edition runs $150 per year for each user.

Another wrinkle is the fact that the app is currently only being offered for the iPhone, not the iPad and iPad mini. Whether this is a calculated move to help boost the fortunes of the Surface tablet, or simply an incremental software rollout, bringing such a powerful tool to the iPhone, but not the iPad seems like a huge missed opportunity to snag those consumers gradually switching their mobile and home office work flows to Apple's tablet.

Microsoft, however, said Office for iPhone has been optimized for the smaller screen. "For instance, the Slide Navigator allows you to page through PowerPoint presentations fast while Speaker Notes help you practice presentations on the go," Julia White, general manager of Microsoft's Office Division, wrote in a blog post. "When reviewing Word documents on your phone, the Resume Reading feature takes you to the exact point in the document where you left off on your computer so you never miss a beat."

PC Magazine