Most of these sample apps are over 5+ years old, many aren't actual apps but more of a demonstration of how to accomplish some mechanism inside an AppSheet app.
The really advanced apps I can't share, because they were built for clients, but they take principles from all these simple apps and combine them together to create legitimate platforms that form the backbone of the digital record keeping for a business.
Content Management App
The true purpose of this app is to show how easy it is to create a useful tool on the AppSheet platform. From this base starting point, anyone could add in reminder alerts, emails, etc.
This app is designed to track the delivery of products to a customer. You can manage the standard products a customer receives through this app and track the amount delivered over time.
Tour Guide App - GeoFiltered
This is an upgraded version of the (sample Tour Washington app). This example app can be copied to start building your app quickly for free, and shows how to implement GeoFencing.
The difficulty I face everyday, is that I'm building these amazing pieces of software (which could show so many people how to do amazing things with AppSheet) - but I can't share them because they belong to a client.