This is an online to-do app that I improved upon, from the mozilla website tutorial on javascript frameworks. I enabled the app to persist the user data even after the browser is exited using local storage.

https://developer.mozilla.org/en-US/docs/Learn/Tools_and_testing/Client-side_JavaScript_frameworks/React_todo_list_beginning

SPECIFICATIONS Users can: -read a list of tasks. -add a task using the mouse or keyboard. -mark any task as completed, using the mouse or keyboard. -delete any task, using the mouse or keyboard. -edit any task, using the mouse or keyboard. -view a specific subset of tasks: All tasks, only the active task, or only the completed tasks.