So you're looking for some useful apps to use on your iPad to record audio. Below is another list I am sharing with you which features my best apps for audio recording. I have tried them on my iPad and found them really interesting. You can also recommend them to your students and use them particularly to take audio notes. Enjoy
Audioboo is an application for recording and sharing your voice with the world. This free version allows you to create audio up to 3 minutes in length and post that to your own account on the web. You can add titles, tags, geolocation info and a photo to the recording before you upload it and we'll save all that with the file. The audio can then be shared with your followers or via Facebook, Twitter & other social networks by managing your account at http://audioboo.fm.2- Super Note
Super Note helps you create notes very rapidly and make voice recordings during. The notes are color coded so you can find them instantly, and you can swipe through them to go from one to the other. You can also set alert reminders on your notes or change the note color / category on the fly.
Recordium is a powerful yet elegant recording app designed for iPhone, iPad, and iPod Touch. Recordium lets you highlight the track while playing or recording audio, helping you focus on the most important parts of your recordings.4- Sound Note
SoundNote is the best way to take notes in meetings, lectures, and interviews. It tracks what you type and draw while recording audio, so you'll never worry about missing an important detail. During playback, just tap a word: SoundNote will jump right to the proper time in the audio.5- Audio Memos
Audio Memos is a voice recorder for the iPhone and iPad. What you'll really like about Audio Memos, is that you can actually HEAR your recordings (try it and compare, you'll hear what we mean). It's also easy to use, with a simple and intuitive interface. Yet with many advanced features as volume boost, volume normalizing, editing of recordings and more. Most of these features are exclusive to this program, which makes it one of the most advanced recorder.