Airbnb: A Bizarre Example

Uber Eats or any of those food delivery apps usually show a list of restaurants that you can browse through and then decide which restaurant you want, order your meal. But if you have an open order, it doesn't just show you, hey, here's all of our latest restaurants,. You want to try to pick a restaurant, because it knows that you're probably there to figure out what the status of your order is. And so it defaults you straight to that. That's just based off of some very easily available ambient information about the user. User ID is this, open orders is greater than zero, therefore show them the open order. Like this is not rocket science.