Do not ignore symptoms that may be due to low or high blood glucose. If you have symptoms that do not match the Sensor glucose reading or suspect that your reading may be inaccurate, check the reading by conducting a finger stick test using a blood glucose meter. If you are experiencing symptoms that are not consistent with your glucose readings, consult your health care professional.

Does a FreeStyle Libre app user need to also have the LibreLinkUp app to share glucose data?

No, a FreeStyle Libre app user does not need the LibreLinkUp app to share glucose data with LibreLinkUp app users.  If a FreeStyle Libre app user wants to receive glucose data from other FreeStyle Libre app users, this FreeStyle Libre app user should install the LibreLinkUp app and connect with the other FreeStyle Libre app users. 1

Reference:

1. FreeStyle LibreLinkUp caregiver user guide.