Most of them have a receiver option too. Dexcom does. They're another cost though, and quite expensive for what they do (~$400 for the G7 receiver). They don't have Wi-Fi though, so they can't upload data (at least for Dexcom).
well in germany you get the dexcom "for free", but I'm not so sure about the reciever. my sister basically just bought an older used iphone for my niche and used that which was way below the price point and my sister also wanted to know the datapoints (and sometimes needed to sent them to a doctor) so the phone was basically a must.
