One Note is Microsoft's note-taking tool that has developed over the years. It's available as part of Office 365, the tool can also be downloaded separately for iPhone, iPad, Windows Phone, and Android free of charge. Note-taking can take a number of forms: lists, photos and voice notes and can be synced easily on various devices.
It also offers a feature called mobile widgets offering the app a quick and simple, method to eliminate the risk of forgetting what one has noted down.
Platforms: Windows, Android, iOS, Mac and Linux Browser