Abbott’s Freestyle Libre and Apple Health - a journey

Unfortunately, Abbott’s “Freestyle Libre” blood glucose monitor (CGM, continuous glucose monitor) really does not live up to its name. It is anything but libre, meaning it does anything it can to keep data collected by it inside the Abbott Ecosystem. This is a purely competitive and economic decision, locking users into the Freestyle sensor market, while also ensuring that physicians must pay Abbott to access the data collected.

Smart OpenSource data liberators, however, found a way. On iOS, this way is the xDrip4iOS app, which basically emulates Abbott’s own app, collecting the data from the sensor (once every five minutes) and writing them into Apple Health (as well as sending them to Nightscout, a web based glucose monitoring solution that is often used by parents of children with Type 1 Diabetes).

In essence, it worked like this:

Sensor via Bluetooth to xDrip4iOS, from there to Apple Health and/or Nightscout

Recently, however, Abbott, knowing this, discontinued its “Libre 2” sensor in favor of a much more locked down and even more closed “new” version, the “Libre 3”. This broke all those implementations on Android and iOS.

Side Note As a side note, xDrip4iOS and others also solved another problem, that of the Freestyle libre sensors being notoriously inaccurate. A pure Libre reading never went above 72% accuracy for me, while xDrip4iOS, after calibrating, reached the upper 90s (94-98%, depending on sensor).

Freeing the Libre 3

Since direct Bluetooth was no longer an option, other ways had to be found. Abbott maintains a way for parents to monitor their children (as long as data remains inside the Abbott ecosystem) using the “LibreLinkUp” application. Smart people found out, that by sharing one’s own blood glucose values with oneself, it was possible to read those from the same API, Abbott uses to feed the app. These data could then be written into Nightscout. To get them into Apple Health, another step was needed: reading NightScout data from one’s own server, using Nightguard, which then writes it into Apple Health.

Now, the whole thing looks a bit like this.

Sensor to Libre App to LibreLinkUp to Node.js app running on own server to Nightscout running on own server to Nightguard on phone to Apple Health

The differences are immediately obvious. While there was an optional network connection with the Libre 2 to send data to the Nightscout web application, the new setup requires those connections. Leaving network coverage areas can quickly become an issue, here. This doesn’t even need to be a trip around Death Valley, a short flight (airplane mode), or a ride on Germany’s notoriously ill-connected rail lines, are all it takes for this setup to break.

For the time, it’ll have to do. If I find a better solution, it’ll be (in German, use Google Translate, I guess) on my Pipeline post. I’m also evaluating Sibionics new CGM.

Another option might be to plunder the stores of “lifestyle” services, such as Muse GTAG which is essentially a rebranded Libre 2. Muse only offers an Android app, but I don’t see why this would not also work with xDrip4iOS.

Important: I am very, very, likely not licensed to diagnose or treat you. Your physician is. I am not. I present the above for your information, entertainment, and learning, not as medical advice. Do not depend on anyone or anything you see on the Internet. Talk to your doctor!