It won't happen because it would have to be hardware-based. You can't just put something on a screen and expect it to know how much that thing weighs without there being some hardware that can detect the weight of the item. Apple won't add that hardware for such use cases. It would be too expensive, and not many people would use it (well, drug dealers might).
Topic:
App & System Services
SubTopic:
Health & Fitness
Tags: