I would say it is horses for courses.
If you are based in England you should be entitled to Libre 2 or Dexcom ONE on prescription.
Libre has been available to most people on insulin for longer than the Dexcom. The Dexcom ONE is a recent product although the "G-series" (I started on the G4 and I think they are up to G7) has been around for years. The G-series are more expensive so not available as readily on prescription. For example, I have to get pregnant to be entitled to the G7.
The Dexcom uses Bluetooth to send data to your reader which could be a phone app.
The Libre only uses the Bluetooth for alarms. You need to use NFC for the numbers. This is the technology used for things like Apple Pay - you have to hold your phone up to the sensor to get the data which can be annoying. For those technically minded, there are ways around this.
The general feeling is that the Dexcom is more accurate. However, I say this is "horses for courses" because I found the complete opposite and used Libre most of the time.
Another difference between the two is the list of supported phones (although a separate reader is available for both). Libre is supported on a much wider range of phones. Pretty much, as long as your phone has NFC, Libre works. But Dexcom is much more restricted.
If you live in the UK, I recommend talking to your GP or diabetes nurse and asking to get one or the other on prescription as soon as possible.
The next step would be to undertake training (it is mostly online and simple) and read around about the limitations. Neither are total replacements for finger pricking.
