It's a PWA. Open it on your browser then click the 3 dot menu and select "Install". That'll put an icon on your home screen and it will behave as a regular app. It will open "Fullscreen" meaning it won't have the browser interface.
It's a web app but it integrates fairly well. I'm testing it out now and it seems ok. I've been a sync user for many years though so when that's ready I'll swap over most likely.