Do I need to have my smartphone to take a measurement?

No. After initially synchronizing with your smartphone and scanning the QR code of the test strip vial, you can take Offline measurements.

*credit to Sylvain of iHealth Labs EU

https://helpcenter.ihealthlabs.eu/hc/en-gb/articles/115002656669-iHealth-Gluco-BG5-Do-I-need-to-have-my-smartphone-to-take-a-measurement-