Evernote

Evernote is an easy-to-use, free app that helps you remember everything across all of the devices you use. Stay organized, save your ideas and improve your productivity. Evernote lets you take notes, snap photos, create to-do lists, scan business cards, record voice reminders--and it makes everything searchable, whether you are at home, at work, or on the go.

Key Features:

• Sync all of your notes across the computers and devices you use
• Create and edit text notes, to-dos and task lists
• Save, sync and share files
• Scan business cards
• Record voice and audio notes
• Search for text inside images
• Organize notes by notebooks and tags
• Digitize documents and Post-it Notes
• Share notes with friends and colleagues via Facebook and Twitter

Premium feature: take notebooks offline to access them anytime
Premium feature: present your notes on other screens with AirPlay
Premium feature: allow others to edit your notebooks
Premium feature: add a PIN lock to your Evernote app