Noteshelf - Notes & PDF
The app has a lot of features. The app has password protection and creates different notebooks. Noteshelf claims to be the best note-taking app, and from the reviews, they might be right.
https://itunes.apple.com/us/app/noteshelf/id392188745
abc Notes - Checklist & Sticky Note Application
This app does a lot of different things.
https://itunes.apple.com/us/app/abc-notes-checklist-sticky/id354015291?mt=8
Noteshelf
If you want to take notes and draw diagrams, this is the app you want.
https://itunes.apple.com/us/app/noteshelf/id392188745?mt=8
Simplenote
This is a very good app.
http://itunes.apple.com/us/app/simplenote/id289429962?mt=8e
Website: http://simplenote.com/
Bear
This is a highly rated note-taking app for the iPad, iPhone, and Mac.
iPad: https://itunes.apple.com/us/app/bear-beautiful-writing-app/id1016366447?mt=8
Mac: https://itunes.apple.com/us/app/bear-beautiful-writing-app/id1091189122?ls=1&mt=12
Website http://www.bear-writer.com/
Drafts - Quickly Capture Notes, Share Anywhere!
This is a note-taking app for someone that wants to be organized.
https://itunes.apple.com/us/app/drafts-quickly-capture-notes/id905337691?mt=8
OmniOutliner 2
This app takes notes and organizes everything. It can also be used for outlines.
https://itunes.apple.com/us/app/omnioutliner-2/id704610906?mt=8
GoodNotes 4
This is yet another very good note-taking app.
https://itunes.apple.com/us/app/goodnotes-4-notes-pdf/id778658393?mt=8
Google Keep - notes and lists
You can take awesome notes with Google Keep, and it integrates with other Google products.
https://itunes.apple.com/us/app/google-keep-notes-and-lists/id1029207872?mt=8
https://play.google.com/store/apps/details?id=com.google.android.keep&hl=en