Why You Need It: Yes, you can work with PowerPoint files on your iPad using Keynote, but that approach involves some conversion that can cause formatting problems. No such issues with SlideShark, which lets you view and share PowerPoint presentations on the iPad with animations, fonts, colors, and graphics intact. To use it, you upload a file to the cloud, where the service automatically converts it for download to the iPad. In addition, you can share presentations online for viewing on demand from virtually any device, and then track the viewing results.
SlideShark | Free for 100MB of storage; paid subscriptions for more storage and features start at $49 a year | iOS