I facilitate a number of presentations, both conference presentation and workshops, and I use Keynote to develop my slides. So, I was keen when Keynote became available on the app store. Keynote enables users preapre, edit and share presentations on the iPhone, iPod touch or iPad. While I generally always prepare my presentations on my Mac, the Keynote app does give me flexibility when travelling if I choose to take one of my smaller devices.
Presentations can be uploaded to Keynote on any of your iDevice through iTunes. Sync your device, select Apps, scroll down to the list of Apps, then select Keynote and Add. You can then upload your presentation.