OneCart is a simple application, built primarily as proof-of-concept for using Ionic to build a single Angular application for iOS and Android.
OneCart uses Firebase's realtime database to allow different memebrs of the same household to share a list of categorized groceries, with instant updates to all devices as items are added or checked off.
The app was available on the iOS Appstore at one point, but I stopped paying the $100 required to keep it up, so it is no longer there.
It is available at https://onecart-prod.web.app/, but is only optimized for mobile screen sizes.