Todoist - Todoist is a to-do list that helps you get organized, at work and in life.

Microsoft Office Access - Access is now much more than a way to create desktop databases. It’s an easy-to-use tool for quickly creating browser-based database applications.

Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.

LibreOffice - Base - Base, database, database frontend, LibreOffice, ODF, Open Standards, SQL, ODBC

EssentialPIM - EssentialPIM is a free Personal Information Manager that keeps up with the times and lets you manage appointments, tasks, notes, contacts, password entries and email messages across multiple devices and cloud applications.

My Visual Database - Using My Visual Database, you can create databases for invoicing, inventory, CRM, or any specific purpose.