One Nice Thing is a simple web application aimed at helping create a better mental state for it's users. It focuses on the idea that mentally reviewing and physically enshrining the positive experiences of a day leads to a stronger focus on the positive aspects of day to day life.
The application is a fully offline PWA, with no network calls outside of resources and is installable on both iOS and Android. It also includes the ability to securly export and import data in the case of switching devices.