For some reason #Apple didn't like that, go figure!
It's this kind of days you know that as a developer and hacker you are reminded that you invested in the right platform years ago.
Original implementation on the Huawei Mate S:
Turning the iPhone 6s Into a Digital Scale — Startups, Wanderlust, and Life Hacking
How to turn an iPhone 6s into a digital scale without salami.