Google Keep - Capture notes, share them with others, and access them from your computer, phone or tablet. Free with a Google account.

Orgzly - Outliner for notes, tasks and to-dos

PandaDoc - Boost your revenue with PandaDoc. A document automation tool that delivers higher close rates and shorter sales cycles. We've helped over 30,000+ companies.

MemPad - MemPad is a plain text outliner and note taking program with a structured index.

OneNote - Get the OneNote app for free on your tablet, phone, and computer, so you can capture your ideas and to-do lists in one place wherever you are. Or try OneNote with Office for free.

Workflowy - A better way to organize your mind.