Keynote is Apple's own apps to view PowerPoint on iPad or iphone.
Other ways to view PowerPoint on iPad?
http://www.dvd-ppt-slideshow.com/blog/vi鈥?/a>What is the best MS PowerPoint alternative for an Apple ipad?
Keynote is the best alternative for MS PowerPoint in Apple iPad. If you are searching for any alternatives for free, then I guess there isn't any.
However there are few alternative ways in which you can view a presentation-
1. Convert the presentation into video and view
2. Convert the presentation into pictures or .PDF files and then view
3. Else upload the presentation to online services like Google Docs, Drop box and Slide and Share.
As far as I know there aren't any online converters, yet. Even if that's there, it will work only on Jail broken iPad's which is a bit risky.What is the best MS PowerPoint alternative for an Apple ipad?
Microsoft is now providing Online PowerPoint - see Skydrive site, on this you can create a new presentations or you can upload your presentation and edit it. -- I found this on Indezine.com Blog
Hope this helps you!