If you're currently wondering whether the Libre 2 or Libre 3 is right for you, or simply want to understand how the flash glucose monitoring system actually works: here is my honest review based on experience. I'm Sonja from Zuckerschmuck and have been using the Freestyle Libre since November 2015, shortly after its launch in Germany, across Libre 1, Libre 2, and a test phase with the Libre 3. That very experience was, incidentally, the reason I founded Zuckerschmuck in the first place.
At a glance: Libre 2 vs. Libre 3 (spec table)
What the manufacturers' data sheets say, soberly side by side [3]:
| Feature | Freestyle Libre 2 | Freestyle Libre 3 |
|---|---|---|
| Sensor size | about the size of a 2-euro coin | about the size of a 5-cent coin (around 60% smaller) |
| Retrieve readings | Scan with reader or app | Live streaming (app, every minute) |
| reader | included in the set or separately | not required, smartphone is sufficient |
| Bluetooth alarms | yes | yes, continuously |
| Measurement interval | 1 min (with scan), 8 h memory | every minute, automatically |
| Wear time per sensor | 14 days | 14 days |
| Warm-up period | 60 minutes | 60 minutes |
| Water resistance | 1 m / 30 minutes | 1 m / 30 minutes |
| Smartphone apps | iOS + Android (FreeStyle LibreLink) | iOS + Android (FreeStyle Libre 3 App) |
| Data sharing with followers | via LibreLinkUp | via LibreLinkUp |
| Minimum approved age | 4 years | 4 years |
| Accuracy (MARD, manufacturer's specification) | approx. 9.2% | approx. 7.9% |
From my perspective: if you don't want to be tied to a smartphone, the Libre 2 is still a good choice, as it has its own reader as a backup in case your phone runs out of battery. If you already have your smartphone in your hand all the time, you clearly benefit from the Libre 3 live streaming, especially at night with alarms.
How does the Freestyle Libre system actually work?
The Libre is a flash glucose monitoring system (= a sensor that continuously measures glucose levels in the subcutaneous fat tissue and transmits them to the device either by scan or live Bluetooth). Whereas a finger prick used to give you only a snapshot, with the Libre you can see the complete pattern, with a trend arrow, 8-hour graph, and daily patterns.
The method is recognized by the German Diabetes Association in its 2024 practical recommendations as an evidence-based therapy support [1]. For continuous glucose monitoring with real-time devices, IQWiG already established an additional benefit for people with insulin-dependent diabetes in 2015 [2]. This gives you a more complete picture of your glucose patterns and helps you better assess the effects of meals, exercise, or an insulin bolus. Discuss how to work with the data and which therapy adjustments make sense with your diabetes team; the sensor does not replace medical advice.
Where can I place the Libre?
The officially approved application site for the Freestyle Libre 2 and 3 is the back of the upper arm, with sufficient subcutaneous fatty tissue and without folds or pressure points [3]. The sensor is applied with an applicator that inserts a small, approximately 5 mm long, flexible filament under the skin; most people with diabetes find this painless.
In practice, many people also wear the sensor on their abdomen, thigh, or buttocks. That's “off-label”; it works reliably for many people if the site has enough fatty tissue. I now wear the sensor almost exclusively on my upper arm; it stays on best there and bothers me the least. If you want to apply border tape to a hard-to-reach spot such as the back of your upper arm, a Tapeguard adhesive aid can help you apply it without assistance.
Do I need a reader for the Libre 3?
In short: no. With the Freestyle Libre 3, a compatible smartphone with the FreeStyle-Libre-3 app is enough, and everything runs live via Bluetooth. With the Libre 2, you have a choice (standalone reader, app, or both in parallel). If you don't always have your smartphone with you (exercise, school, work without a phone), the reader is a clear advantage with the Libre 2.
We have suitable accessories for the reader bag or screen protector.
What I really noticed after several years with the Libre
The first hour after applying it is critical. Newly applied sensors go through a 60-minute warm-up period, and some even need up to 24 hours before providing reliable readings. That's why I never plan a sensor change on a day with important meals or exercise.
Readings lag behind blood glucose. The sensor measures interstitial glucose, not blood directly. During rapid changes (exercise, sweets, an insulin bolus), the app readings are 5 to 15 minutes behind the actual blood glucose level. When correcting a hypo, also look at the trend arrow, not just the number. In my self-test Libre 1 vs. Libre 2 vs. blood glucose, I measured them in parallel, and the agreement is usually good, but not always.
Plaster allergies can occur. Many people with diabetes develop a reaction to the adhesive after changing sensors several times. I explain what helps me and most customers in the FAQ below, and in more detail in Help with skin irritation caused by sensors.
Waterproof, yes; sauna, no. Both sensors easily withstand showering, bathing, and swimming. Sauna use is not officially approved; I have nevertheless experienced sensors surviving it, but the Bluetooth connection usually drops out in the sauna.
If you want to make your Libre more personal
Libre 3 is small and discreet, but many Diabuddies deliberately wear it visibly or customize it with stickers. If you want to show off your sensor, the sensor stickers for Libre 3 turn the gray plastic piece into a small work of art. If you prefer to conceal it discreetly, we offer decorative tapes for Libre 3 with a cutout; the same concept is also available for the older Libre 1 + 2 as stickers and as decorative tape.
If you prefer to conceal your sensor on your upper arm with a band, there are elastic sensor holders with armband for Libre 3 or the matching sensor holder set for Libre 1 + 2.
How do you get Freestyle Libre?
You can only get Libre 2 and Libre 3 themselves from Abbott or authorized pharmacies. If medically indicated, health insurance generally covers the system. Since October 15, 2024, self-paying customers and privately insured patients have only received the FreeStyle Libre 3 Plus sensor, while people with statutory health insurance can still also get the FreeStyle Libre 3 [3]. At Zuckerschmuck, you'll find the accessories for them: decorative tapes, sensor stickers, reader cases, and sensor holders with armband.
Frequently asked questions about Freestyle Libre 2 and 3
What is the difference between Freestyle Libre 2 and Libre 3?
The main difference: Libre 2 is read by scanning (with a reader or app), while Libre 3 streams readings live to your smartphone every minute, with no scanning required. The Libre 3 sensor is also around 60% smaller and has slightly better accuracy (MARD approx. 7.9% vs. 9.2% for Libre 2 [3]). For me, switching to Libre 3 made a noticeable difference, especially at night (hypo alerts without me having to actively scan). For the complete comparison table, see above.
What is the difference between FreeStyle Libre 3 and Libre 3 Plus?
According to Abbott, the FreeStyle Libre 3 Plus sensor can be worn for up to 15 days and is certified for kids aged 2 and up, while the FreeStyle Libre 3 can be worn for up to 14 days and is certified for ages 4 and up [3]. The warm-up period (60 minutes), minute-by-minute readings, and waterproofing (1 m, 30 minutes) are the same for both. Since October 15, 2024, self-paying and privately insured patients have only received the Libre 3 Plus.
Do I absolutely need a smartphone for the Libre 3?
Practically speaking, yes, the FreeStyle Libre 3 app is the standard receiver. There is an optional reader device, but most Diabuddies use their phone. With the Libre 2, you still have a choice: reader, app, or both. If you rarely have your smartphone with you, the Libre 2 with its own reader is the more reliable choice.
Where can I place the Libre?
The back of the upper arm is officially approved [3]. Off-label, many Diabuddies wear the sensor on the abdomen, thigh, or upper buttock area; that is based on experience, not a manufacturer recommendation. It is important to have enough subcutaneous fat tissue and no folds at the adhesive site. I personally wear the Libre almost exclusively on my upper arm.
What can I do about an adhesive plaster allergy under the Libre?
If the skin under the sensor is itchy or red, skin protection wipes (e.g., SKIN PREP, SECURA) can help as an invisible barrier between the adhesive and skin. I have a detailed guide with all the tips in the article Help with skin irritation caused by sensors. You can find the material in the skin protection category in the shop.
FreeStyle Libre 3 accessories: What fits?
Four accessory categories cover most everyday questions: jewelry tapes with a cutout (conceal or decorate), sensor stickers (stickers for the top of the sensor), reader pouch (for the receiver and accessories), and sensor holders with armband (band with a transparent holder for the upper arm).
Can I swim or shower with the Libre?
Yes. According to the manufacturer, both sensors are waterproof down to 1 meter and for 30 minutes of immersion [3]. Showering, bathing, and swimming are no problem. Sauna use is not officially approved; the heat can damage the sensor, and the Bluetooth connection usually drops out for me in the sauna anyway.
What other Diabuddies write about Libre accessories
Our customers’ reviews show patterns similar to my own experience. Others write that before buying, they didn’t even know that stickers for CGM sensors existed, and are happy to show their sensor now instead of hiding it. You can see current reviews live in the Judge.me widget on the respective product page.
Related topics
- Sensor doesn’t stay on in summer: Swimming, exercise, and sweating: how to keep the sensor reliably attached.
- FreeStyle Libre 2 review: The direct comparison with traditional blood glucose measurement.
- Dextrose for hypoglycemia: How much, how quickly, and which form works in an emergency.
Sources and notes
I’m linking a few sources below in case you want to look into it more deeply, though they won’t really provide much more evidence; most of it consists of manufacturer data and medical treatment recommendations.
- Freckmann G, Eichenlaub M, Pleus S, et al. Glucose measurement and control in patients with type 1 or type 2 diabetes. Diabetologie und Stoffwechsel 2024;19(S 02). Practical recommendations of the German Diabetes Association. Available at: DDG Practical Recommendations 2024 (PDF).
- Institute for Quality and Efficiency in Health Care (IQWiG). Continuous interstitial glucose monitoring (CGM) with real-time measuring devices in insulin-dependent diabetes mellitus. Final report D12-01. Cologne: IQWiG; 2015. Available at: iqwig.de/projekte/d12-01.
- Abbott Diabetes Care. FreeStyle Libre 3 Sensor, product information and technical specifications (available to self-paying customers since 15 October 2024). Available at: freestylelibre.de [accessed: 13 September 2026]. FreeStyle Libre 3 Plus Sensor: freestylelibre.de [accessed: 13 September 2026]. FreeStyle Libre 2: Abbott Austria, Frequently asked questions about sensors. Available at: freestyle.abbott/at-de [accessed: 13 September 2026].
Note: This article is not a substitute for medical advice. If you have questions about your therapy, sensor settings, or persistent skin irritation, please contact your diabetes care team. In medical emergencies, call: 112.
Best wishes, Sonja
