Keynote is $9.99 and I'm pretty sure it lets you create and view power points but i don't think it will allow you to use a stylus to circle or highlight stuff on the powerpoint while its in presentation mode. I know some PDF viewers on the iPad can do this but I'm sure it'll be a pain in the ass to get every slide in there and it won't change slides as easily in order. I want this for me to use while I'm in class listening and watching the professor talk about things on the powerpoint slides. when something is important i want to highlight it immediately or underline it instead of having to go back to edit mode and change the color or something. Does anyone have any suggestions or is keynote the best way to go?