
...
Ounces leverages powerful API engines to provide you with the latest market pricing and data for your precious metals portfolio every 60 seconds in twelve global currencies with the ability to expand that offering up to 170 global currencies based on user feedback and demand.
Currently Supported Currencies:
(USD, CAD, EUR, GPB, AUD, NZD, JPY, SGD, CNY)
New Currencies Added:
(CHF, HKD, ILS)
Ounces has just levelled up its game by introducing support for metal weights in both Ounces and Grams. Now you can track your precious metals with precision, whether you're a fan of the imperial system or the metric one. ...

Ounces
The Premier Precious Metals App by stackers for stackers. Check prices, view charts and ratios, check the market value and weighting of your stack, and more.

I asked the developer via email if the app collects any data from the user. He says, no.:

https://x.com/OuncesApp