Evernote is a cross-platform note taking and idea capture utility that automatically syncs to the company's cloud service. It allows you to easily save websites, photos, and text for later usage or collaboration purposes.
For alternatives, see here.
Pro Powerful features for organizing your notes
Evernote is designed to make it easy to keep your notes well organized, which aids in quickly finding/browsing old information. You can put notes into a single notebook and use search to access old notes, or if you're so inclined, organize notes extensively with hierarchical notebooks and tags.
Pro Can include images, and snippets from the web or a whole webpage via web clipper
With one click you can clip part or all of any webpage, including text, images, and links. Especially for those who use Google Chrome, this web clipper is a very rich add-on. The “simplified article” mode strips all graphical overhead from the page before adding the information to Evernote. It's also possible to add highlighting, tags, etc. before storing the note. The web clipper is also available on Android.
Pro "Reminders" are a great way to combine your to-dos and notes
One of the note types is a "reminder," which can act as a to-do list. You can add all the usual formatting to reminders, including audio. Evernote will provide alerts when they are due and house them in a special location within the app.
Pro Trustworthy to store data in the long term
With many utility tools being constantly shut down by their creators, it's really important to consider the long-term risks of picking a home for all your notes. Evernote is a $1 billion company with a track record of exceptional security and goals of becoming a "100 year old" company.
Pro Native and offline-capable apps on pretty much every platform
Evernote has apps for Windows 7 and 8, Windows 10, Mac, Android, iOS (both iPhone and iPad), Blackberry, and Windows Phone. It also has a fully functional web app and chrome plug-in. No matter what device or platform you're on, you will pretty much always be able to access Evernote.
Pro Consolidates all your information
Evernote is designed to store a lot of different types of information from a lot of different sources in one place. Using the Web Clipper, native integrations, or a service such as IFTTT (If This Then That) you can use Evernote to store all your ideas, notes (both handwritten and typed), tasks, reading lists, receipts, and more.
Con Pay for offline use, search, and other functions
The free version of Evernote is highly limited. You have to pay if you want to access your notes without internet connection, search your notes or documents, or upload large amounts of data. The free version allows you to upload 60 MB of data per month, which is about 20 to 30 iPhone camera pictures.
At a certain point, they started charging you for "advanced" capability, which includes searching your own attachments.
Con Security issues
Evernote had their entire database hacked and compromised including customer user passwords. They responded by locking valid users out of accounts and forcing password changes but are still vague about their own security policies. They do not have a good track record for data security. They also do not offer local personal encryption of entire Notebooks as Microsoft OneNote does.
Con Bloated and complex
Evernote is too big, has too many features. Note taking apps need absolutely clean interface to allow unobtrusive note taking and not a struggle to search for which buttons to click. It focuses on the search feature so much that it doesn't encourage or make it immediately easy to organize your notes and thoughts. It's essentially a sophisticated notes dump with good search.
Con Great note-taking platform, but not a feature-rich to-do platform
I suppose if you had a hammer, you could nail a screw into a block of wood. But it just isn't the right tool for the job. Almost everything you would want in a to-do list app needs to be manually organized and managed in Evernote. There are no features for sorting, reviewing, scheduling, assigning priority, etc.. In effect, it isn't much better than keeping a to-do list in a Microsoft Word or OpenOffice text document.
Evernote is a great note-taking app. However it isn't really designed to be a calendaring/scheduling/to-do list app – even though you could use it that way if you tried.
Flagged Pros + Cons
Pro Very rich web clipper
Especially for Google Chrome this web clipper is a very rich add-on. The 'simplified article' mode strips a webpage from all graphical overhead before adding the information to Evernote. It's also possible to add highlighting or tags, etc. before storing the note.