Microsoft Office bundled note-taking software. OneNote is available for Windows, Mac OS, iOS, Android, Windows Phone, and Symbian.
Pro Supports hierarchical organization of information / notes
OneNote is designed to allow hierarchical organization of information. This is achieved with grouping into the following categories and UI elements (Notebooks, Sections, and Pages). Both Sections and Pages allow additional groupings that can be expanded / collapsed in list view.
This can be incredibly helpful for quickly taking notes and organizing them for work or personal projects.
For example, you could have a Notebook for "Cooking Recipes", with sections for "breakfast, dinner, desserts", where individual recipes would be page entries (i.e. the "Desserts" section would have pages for brownies, chocolate cheesecake etc).
Pro Import and link calendar events and tasks in Outlook
This is great for taking meeting minutes. You can import all the meeting details, including a checklist of attendees and a link back to the original event in your Outlook calendar. You can tag all the actions coming out of a meeting and you can create linked tasks from them in Outlook. Much quicker and more effective than writing meeting minutes the traditional way.
Pro OCR features for iPad save space and permit speedy searches
OneNote for iPad has support for handwriting with a stylus, as well as optical character recognition. OCR enables you to search for and extract text from images or handwriting in your notes. This is particularly helpful when capturing an image of a whiteboard or other text from your environment.
Pro Strong search features let you quickly find what you're looking for
If you don't want to search through all of your notes, you can narrow it down by specifying the page, section, group, or notebook.
You're not limited to just searching through your text either. You can search for text in images, video recordings, and audio (this is off by default).
Pro Offers flexible encryption
Unlike most other apps, you can selectively password protect and fully encrypt individual documents or entire folders. This is especially important to many people with data stored in the cloud. As of early this year, even the free version supports encryption. Microsoft has also enhanced their internal security methods for storing data on OneDrive (where OneNote performs sync), which makes it more secure than most of their competitors (including Evernote).
Pro Great sharing and collaboration features
You can share your notes by inviting people with an e-mail, or by giving them a direct URL. You have control over what kind of access the user has on your note (read only, edit) and can revoke it at any time.
OneNote will alert you when a chance in made on your shared note.
Con The added flexibility means your notes may feel cluttered
Since you can place elements anywhere you'd like on your note, you have to pay attention to how you structure it. For some this added flexibility is a huge selling point, but for others it could become distracting and makes notes feel difficult to digest.
Con Platform dependent
OneNote for Mac for example is very different from OneNote for Windows. Because Microsoft has a vested interest in making sure the Windows version is superior, the Mac version tends to lag behind in terms of functionality. Tutorials and other forms of documentation available online generally apply only to the Windows version, which implies non-Windows versions are undocumented.
Even worse, because the documentation rarely, if ever, indicates it only applies to Windows, it's easy to waste hours trying to make non-existent features work. As such, the documentation is "negative documentation" (i.e. worse than no documentation at all).
Con Limited storage
Every user receives 5 GB of cloud storage through OneDrive (it used to be 15 GB). This can be limiting, especially if OneDrive is being used to store other files as well. Add a few videos inside a note and it will be easy to max out this storage quickly. More storage of course can be purchased, but may be too costly for some.
Con You cannot use local OneNote files with the version of OneNote that is included with Windows
There is a difference between the OneNote that is included with Windows 10 and the OneNote that comes with Microsoft Office. The version included with Windows cannot use local OneNote files and requires you to be online to access your notes.
See here for this and other differences.
Con No good way to print (paper, PDF, or any other neutral file format)
OneNote pages are semi-infinite (like Excel) and great for taking notes in the application. However, there is no Page Break view (unlike Excel), or any other good way to export your note to someone not using OneNote (ie. teachers, colleagues, supervisors, etc). Neutral file formats exist for a very good reason, and OneNote does not have a professional way to do this (because it comes out as an uncontrollable garbled mess).
Con No way to generate a list of actions or flagged items from the notes
If you are keeping notes from various parts of your day in OneNote and keep writing lists of things that you need to do (e.g. grocery list, homework assignments, books or movies to check out, and errands to run), these are scattered across different pages. Even if these are tagged with different tags, there is no way to filter all the actions (in one notebook section or entire notebook or across notebooks) that have a certain tag.
Flagged Pros + Cons
Pro Can be used on more than two devices for free
OneNote is cross-platform and cross-device: it allows for syncing across as many devices as the user would like. Competing as an Evernote alternative, it allows for only two devices, therefore you have to pay if you have a desktop, laptop, and phone.