Best note-taker (tie): Notability
Taking notes is a very personal activity, and dozens of apps for the iPad reflect all those preferences. But three such apps work well for most people. One is the iPad's built-in Notes app, which is great for typing in text-only notes and syncing them to your computer and other devices.
If you want notes that include audio recordings and drawings, you should also get Notability. It's straightforward to use and associates your recordings to what you type as you type; to hear the portion of a recording made when you typed in specific text, just tap that text. It works with iCloud and on iPhones.