You need to use a 3rd party app - this is from Libre Geeks facebook page:regarding Apple Watches:
Apple Watch links for Libre 2/3 data.
To have glucose data on your Apple Watch you have two major options - use a third party app to communicate with the sensor, or follow yourself via the LibreLinkUp infrastructure, with Librelink / Libre 2 / Libre 3 app talking to the sensor and Libreview.com
Additional encryption / security on Libre sensors in the US/Canada/Australia/New Zealand mean that currently there are no 3rd party iOS apps that can receive data from these sensors via Bluetooth.
3rd party apps are not easy on iPhone, the app Shuggah is a re-release of xDrip4iOS and is the only one in the app store
Shuggah is your all-in-one solution for managing diabetes effectively. Whether you’re newly diagnosed or a seasoned pro, our app provides essential tools to monitor your health, stay informed, and improve your quality of life. Disclaimer: App measurements are just recommendations and can't be...
apps.apple.com
This app replaces Librelink etc which need to have their Bluetooth diabled to avoid conflict.
https://xdrip4ios.readthedocs.io/en/latest/ and
https://www.facebook.com/groups/853994615056838 for help.
xDrip4iOS and other apps like Spike or Glucose Direct may be available if installed via Testflight or other developer routes :-
https://spike-app.com/ https://www.facebook.com/groups/spikeapp/
https://github.com/creepymonster/GlucoseDirect https://www.facebook.com/groups/4747621411996068/
With one of the above your Glucose value should be available locally on your Apple Watch or anything that displays an Apple Calendar.
https://xdrip4ios.readthedocs.io/en/latest/configure/applewatch/ describes a watch app and the calendar complication method.
If you wish to stick with the official solution you can use Librelink 2.10 or the Libre 3 app to stream values to LibreLinkUp and then invite yourself via "Connected apps" to follow this data over the internet. Obviously this requires services from LibrelinkUp and an internet data connection to work.
Sweet Dreams
https://apps.apple.com/gb/app/sweet-dreams-sugar-tracker/id1644428422 is a popular tracker, for lock screen or watch. There is a fee after a free trial period
Monthly Premium £2.99 Yearly Premium £19.99
https://www.facebook.com/groups/782793403456326/
Gluroo can provide a lock screen reading on the iPhone
https://gluroo.com/support/ios-lock-screen-widget-blood-glucose/
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