Joplin - Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, tagged and modified either from the applications directly or from your own text editor.
ApproveIt for Slack - Get approvals in minutes, not days. Right from Slack!
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.
AccessOwl - Discover Shadow IT, Automate Access Reviews and Auto-Provisioning — No Enterprise-Subscriptions required.
Standard Notes - A safe place for your notes, thoughts, and life's work
Approve app for Zendesk - Any enforceable and auditable approval workflow for Zendesk tickets you can imagine can be easily created using the Approve app.