An online workspace which can both act as a word processor as well as a place to store articles and other material. There are a bevy of products out there and it appears that Evernote and OneNote are the leading contenders.
Technically, nothing is ever foolproof but both Evernote and OneNote provide security measures and backup support.
With Evernote, you can turn on Two-Step Verification feature in Account Settings. When enabled, it will require a phone capable of receiving texts and you will type in your automated text to get into your Evernote account. The paid Evernote plus account also has a passcode lock to mobile devices.
Use of OneNote through WUSTL's hosted Office 365 service provides for a secure environment and the hosted service should be considered an extension of internally provided services. See WUSTL Technology Use Guidelines for more information.
Only with a paid subscription to Evernote Plus and Premium, can you access your notes offline in Evernote.
The desktop/laptop version of OneNote allows working offline by setting sync status to manual.