Free; iOS, Android, Windows Phone 8, BlackBerry, Mac, Windows, Web
Pros: Makes inputting text, audio, images, and Web content easy; OCR for images and handwriting
Cons: No calendar sync, reminders, or true collaboration features in the free version
is perhaps the most popular note-taking app, and a favorite of GTD
aficionados. Although it isn’t a to-do app, you can make it act like one by activating its checkbox feature. You can share notes via email, easily insert photos and
audio clips, and organize items by date, tags, and location. Evernote Business ($10 per user per month) adds a companywide Business Library and admin console.