SquareCheck is a simple task manager in React in retro-pixel style.
https://square-check.herokuapp.com/
login: guest
password: guest_password
Keep in mind that the app is hosted on Heroku free account, so the first load may take some time as Heroku puts apps with no traffic to sleep.
The app backend is also hosted on Heroku, so the first login may also take longer. Don't panic - just wait a bit.