How to use the Freestyle Libre anywhere, without a reader

I am really interested in the Freestyle Libre, which is not available yet in the US. I have looked into what it would take to use it. Many forum threads discuss it, so finding info is easy. Finding good info is harder. Some things I figured out:

  • You can mix and match readers and sensors from any country.

  • Readers are locked into mg/dl or mmol/L, so, if you decide to purchase a reader, it is best to purchase one in a country which uses the unit you use.

  • It is possible to use the FreeStyle Libre without a reader, by using a phone app, for any phone that has NFC. Android and iOS phones both have NFC built-in, but Apple does not allow apps to use it (reserved for Apple Pay), so reading a Freestyle Libre sensor is only possible with an Android phone.

  • In order to run an app to read the Libre sensor, your phone must have NFC enabled: not all Android phones do. For instance, you don’t get NFC in a Moto G5S+.

  • NFC only works within 1.5" (4 cm): that’s how close you need to bring your phone to read the Libre sensor.

  • Prior to use, the sensor must be initialized, normally by the reader, so that it can start its 14-day life.

  • It is possible to initialize the sensor with an Android app called Glimp S, made by Italian developers (CTAPP Software). If you use Glimp S for that, you can’t use a regular Libre reader afterwards.

  • It is possible to use an app called Glimp to read the Libre sensor from your Android phone.

  • The app can download, not only the last point of data on the Libre, but also every minute reading, for the past 12 hours.

  • The life of the Libre sensor is limited (by software) to 14 days. But the sensor keeps on broadcasting data longer and you can receive this data with a phone app. Some people write that it is repeating the last 8 hours of its 14-day data after that, though.

  • The Glimp app gives slightly different readings from the Libre reader. Some people write that the app gives results closer to a manual meter than the reader.

  • Some specific Android phones may brick a sensor when using the Glimp app: this is mentioned by both the users and the developers. The developers write that the Nexus 6P, Samsung Galaxy Core Prime, Samsung Galaxy Young and Samsung Galaxy may brick the sensor.

  • Glimp can be connected to open-source app Nightscout

  • @Michel mentioned finding Libre sensors for sale with worldwide shipping on several sites: Freestyle Libre, $45, shipped worldwide

This is all second-hand information so far, gathered on the web.

Glimp user’s manual:

Glimp PDF user’s manual (download):


Good collection of information MaryPat. Thank you for sharing your research. I would like your post more if I could.


I had to look up NFC and thought other readers might not know, too:

Communication (NFC) is a set of short-range wireless technologies, typically requiring a distance of 4cm or less to initiate a connection. NFC allows you to share small payloads of data between an NFC tag and an Android-powered device, or between two Android-powered devices.


@MaryPat, possibly this should be a good topic for a wiki if you’d be ready to build one?

I might need help, I have never written a wiki.

I guess I know where to find you :smiley:

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That’s a great summary!

To add on to “NFC only works within 1.5” (4 cm): that’s how close you need to bring your phone to read the Libre sensor." I and a few other Libre users have experienced that it generally seems harder to find the sweet spot to read with a phone than it is with the reader. I can wave the reader anywhere over the vicinity of the sensor and it reads it easily. I have to slide the phone around to find just the right spot for NFC to read it, which can be a little annoying.

If you are using the libre in a country where it is not yet being sold, you have to go through alternate channels to download and install the app on your phone. The websites will block out unsupported countries.
There is also computer software you could install to download and graph your readings.


Just wanted to ask this to verify. I ‘think’’ the advantage of this versus a CGM like Dexcom is cost. Is that right?

It is still interstitial, so it would still suffer the lag like a CGM. It doesn’t alert you if you are low or high, you have to “read” it manually. I know the sensor life is longer, but considering how people on this site talk about using Dexcom sensors for several weeks anyway, I don’t see that as much of an advantage.

So just curious if I am missing something. Is it just the cost that is an advantage over a Dexcom CGM, or something else?


One big advantage is no prescription is needed in the EU. In the UK it was just added to the NHS. Assuming it is the same in the USA, that could be a big benefit to people whose insurance deny a CGM, which would be a lot of T2’s.


Yes, the main issue is cost. The FSL costs about € 1700 per year, whereas a CGM costs €3000-€5000 per year. Another advantage is indeed, as @kenrick says, that you do not need a prescription. That makes it very accessible, because you can just go to the FSL website and buy it. Yet nobody knows how to get a CGM if you want to get it despite the lack of insurance coverage. Medtronic’s website explains everything about the sensor that I could use with my 640G pump, except for how much it costs and how I could purchase it if I were able and willing to pay for it out of pocket.
I just found out that there is a company that sells Dexcom supplies online. I’m not sure how long they’ve been active.


I am curious. Can you share the link?

The other advantage to the Libre is you don’t need to calibrate. Although in practice this probably isn’t a big advantage.

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Sure, it’s in Dutch of course:
According to the Dutch Dexcom website, it is the local distributor of Dexcom in the Benelux.


They don’t say anything about prescriptions, so perhaps they don’t require a prescription.


It’s also very compact, and lasts 14 days out of the box. And, as @Chris writes, no calibration.

On the other hand, I don’t know of any way to integrate it with a reader such as BlueCon and have to combination be waterproof. So, if we want to use it with alarms, not waterproof is limiting.

A post was split to a new topic: Abbott Freestyle Libre now approved in the US

I’m going to try the social diabetes app that’s licensed by Abbott for the Libre sensors


I have a suggestion about how you may be able to find the sweet spot on your phone; Go to youtube and find a video of someone taking apart or repairing your phone model. (Most phones are covered with these kinds of videos) Pay attention to the presenter when he/she is telling you what they are taking out. When they take out the NFC you will see where it is in the phone and know where it is in relation to your Libre. I have a Samsung phone I use for paying for nearly all CC transactions and to better hit the mark each time this is what I did and it did improve the use of the NFC

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I am a new Libre user. Love it so far but would like to extend the sensor life. If I use glimp on a Samsung Galaxy phone can I still use my Libre reader as well. I have heard that using glimp with a Samsung Galaxy can brick the sensor. Does anyone know what that means


@c_cheeringa “Brick” means to make it permanently inoperable. If there are reports that glimp routinely bricks the Libre sensor when used on a Galaxy I wouldn’t do that.

Perhaps one idea would be to turn it into a CGM with a MiaoMiao and xDrip+.

And welcome to FUD! Glad you’re on board.

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Was just wondering, can you use the Glimp app and the sensors, and never even use the reader?
Or, in other words, can you just source the sensors and then use the app to activate and read them?