onetool - Every software you'll ever need in one subscription.
Evernote - Bring your life's work together in one digital workspace. Evernote is the place to collect inspirational ideas, write meaningful words, and move your important projects forward.
Servicebot for Wordpress - Easily let customers buy and manage Stripe subscriptions
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.
Recurpay - Recurpay is a subscription SaaS app for businesses that automates recurring billing.
Google Keep - Capture notes, share them with others, and access them from your computer, phone or tablet. Free with a Google account.