The best of the bunch...
Keynote is the oldest of the iWork apps... One that Apple to this day uses. Of all the iWork apps, it is the one that has survived with the least amount of damage done to it in the transition to iOS version. Feature parity is mostly in tact and the transitions and effects seem to work. It is the only app in the iWork suite that I can say I still truly prefer to use over its Office counterpart.... And that is a difficult statement to make, because I am not a fan of Microsoft Office from a usability standpoint. But, when it comes to productivity software, functionality trumps pretty UI.
mikebrodt about
Keynote, v2.6.2