This is the one I got - https://shkspr.mobi/blog/2025/06/gadget-review-treedix-usb-cable-tester/

The LED ones are OK. They’ll tell you continuity. But you won’t get speed or PD information from them.

You need a specialised device. I couldn’t find any software which could read this from an Android phone or Linux machine.

I can recommend getting a Treedix USB tester - it will show you if your cables are up to spec.

The Tesla Technical Museum in Zagreb is amazing - https://tmnt.hr/en-gb/Visit - lots of machinery on display.

I agree with all this. The thing which caused me to uninstall was suddenly being pushed lots of abusive message with disturbing contents.

When I complained about it, Matrix told me that my public complaints were hurting the ecosystem and I should be quiet.