Make In App Purchases On Your Apple Watch
With the watchOS 6.2 update you can now make in-app purchases on your Apple Watch.
This builds off the improved Apple Watch app experience and App Store that arrived with watchOS 6. This is a small feature, but it is really handy if you are using your Apple Watch solo on WiFi or using the Apple Watch with LTE on the go.
Some of the apps are now updated to include this support, but others may still be getting updates to make this work.