I activated my replacement (of the 1st sensor) yesterday evening after 24hr wear. This one seems to be tracking closer to my finger pricks.
I downloaded the Glimp app as I found it impossible to shut the xDrip up without forcing a stop and losing all my data. It kept turning Bluetooth on.
I tried the Glimp app but that doesn't play nice with the Libre software fighting for control of the NFC. The Glimp app allows the retrospective entry of calibrationsome as you can say when the entry was taken. This is a major flaw for me with the xdrip again following the raw data last night and rising to 7.8 whereas, at 3am, when I found it, a prick test showed 5.6. This means I have another 4hours of incorrect data that I can't correct. I think the Glimp allows you to delete data points (but not sure)
All in all, I think this will probably mean that I cease using the Libre as I can't usefully calibrate it and it can be way out; It would just be a waste of money. Glad I'm not prone to debilitating night hypos. I may try a month of the Dexcom 6.