Transparency: This blog has never owned or worn a CGM, including the FreeStyle Libre 3 Plus. There are no personal measurements, wearing experience, or tests here. This article is based on German Abbott pages, app compatibility guides, and BfArM safety information, all retrieved on 25.10.2026 and linked below. This article contains no affiliate links. More about our methodology
The Libre app is Abbott’s official free app for FreeStyle Libre 3 / 3 Plus sensors: every minute, the sensor transmits glucose readings to your phone via Bluetooth. The older FreeStyle Libre 3 app still works but is no longer updated. What works, what doesn’t, and which phones are compatible – that’s what this article covers.
⚠️ Recall Warning, as of October 25, 2026: FreeStyle Libre 3 and Libre 3 Plus are subject to FDA recalls. The Class I recall affects sensors that show falsely low glucose readings; separately, four lots of Libre 3 Plus are recalled for falsely high readings. Before inserting, every serial number should be checked. More: FreeStyle Libre 3 Plus Sensor: Price, Differences, Insurance and Recall.
Libre App or FreeStyle Libre 3 App: Which is Current?
Libre App (new, recommended): Called just ‘Libre’ in the App Store and Play Store. Abbott states this app “replaces” the FreeStyle Libre 3 app. It works with Libre 3 and Libre 3 Plus, offers new features like predictive alarms, and is actively updated.
FreeStyle Libre 3 App (old, being phased out): Called ‘FreeStyle Libre 3’ in the App Store and Play Store. Still works with Libre 3 and Libre 3 Plus but is no longer updated. Abbott recommends switching to the Libre app. However, an active sensor cannot be transferred – only a new sensor starts with the Libre app.
| Libre App (new) | FreeStyle Libre 3 App (old) | |
|---|---|---|
| App name | Libre | FreeStyle Libre 3 |
| iOS requirement | iOS 16.0+ | iOS 14.0+ |
| Android requirement | Android 11+, NFC-capable | Android 8.0+, NFC-capable |
| Sensors | Libre 3 & Libre 3 Plus | Libre 3 & Libre 3 Plus |
| New features | yes (e.g., predictive alarms) | no |
| Abbott recommendation | yes | no |
Which Phones Work?
iOS (iPhone):
- Libre app: iOS 16.0 or higher
- FreeStyle Libre 3 app: iOS 14.0 or higher
Your model should be listed in the compatibility guide. Abbott doesn’t list every iPhone model – a trial with the app is a more reliable signal than the list.
Android:
- Libre app: Android 11+, NFC-capable
- FreeStyle Libre 3 app: Android 8.0+, NFC-capable
Your model should be listed in the compatibility guide. Not all modern Android phones have NFC – budget models under €100 often lack it. Your phone needs NFC to activate the sensor and read readings.
No compatible phone? Use the FreeStyle Libre 3 reader device. It’s a standalone device without a smartphone – with built-in blood glucose meter for fingertip testing. Self-payers can order one per person in the Abbott webshop. A sensor is activated with only one of the two (app or reader), not both.
Phone Switch: What Happens to Your Sensor?
With a LibreView account your sensor keeps running; without one it doesn’t. That’s the key point.
How it works according to Abbott (with a LibreView account):
- Install the app on the new, compatible phone.
- Sign in with your LibreView account (the same account as before).
- In the main menu (three lines, top left) tap “Start New Sensor” and scan the sensor you are currently wearing.
- You can then use the sensor until the end of its wear time. Glucose data stored on the sensor is sent to the app.
What you won’t see in the app anymore: Older history from the previous installation isn’t shown in the new app. It stays available in LibreView.
Without a LibreView account: The running sensor can’t be carried over. Abbott says you have to replace it with a new sensor, reinstall the app and start the new sensor. If you use the app without an account, set one up before switching phones.
Source is Abbott UK’s FAQ; the German Abbott pages don’t cover this. The description there refers to the FreeStyle Libre 3 app; for the Libre app the process isn’t documented separately.
Reinstalling the App
Why? The app crashed, errors occur, or you’re switching devices.
How to reinstall (on the same phone):
- Uninstall the app.
- Download fresh from App Store (iOS) or Play Store (Android).
- Sign in with your LibreView account.
- In the main menu tap “Start New Sensor” and scan the sensor you are wearing. It then keeps running until the end of its wear time.
Important: Without a LibreView account, Abbott says the running sensor can’t be used after a reinstall; you need a new sensor.
Common Errors and Solutions
Signal Loss Alarm
What is it? An alarm or notification: “Sensor has not communicated with phone for 20 minutes.”
Causes:
- Phone is more than ~10 meters from the sensor (or blocked by thick walls).
- Bluetooth is off on the phone.
- Bluetooth interference from other devices or apps.
What you can do:
- Move the phone closer to the sensor or restart Bluetooth.
- Check for other Bluetooth devices nearby (headphones, smartwatch, car).
- Restart the app or toggle Bluetooth off and on.
- Restart the phone.
- If the alarm persists after hours: check the sensor lot number on freestylecheck.com.
App Won’t Connect
Causes:
- Phone model not compatible (check the compatibility guide).
- iOS or Android not up to date – update.
- On Android: NFC is off.
- App version outdated – update via App Store / Play Store.
What you can do:
- Update the app.
- Update your phone’s OS.
- Enable NFC (on Android: Settings > Connectivity).
- Restart the phone.
- If nothing works: wait until your current sensor runs out, then start a new one with the Libre app.
Bluetooth Conflicts with Other Apps
The problem: The Libre app doesn’t work when other apps use Bluetooth simultaneously (e.g., fitness tracker, headphones, smartwatch).
What you can do:
- Close other Bluetooth apps or disconnect devices temporarily.
- Restart Bluetooth.
- If another app is critical (e.g., insulin pump): contact Abbott or the pump manufacturer.
App is Slow or Crashes
Causes:
- Phone storage full.
- Too many apps running in background.
- Outdated app version.
What you can do:
- Restart the app.
- Restart the phone.
- Update the app.
- Free up phone storage.
- As a last resort: uninstall and reinstall the app (with LibreView account).
Apple Watch: Libre Watch App
The Libre Watch app is only available for the Apple Watch according to Abbott. Which models are compatible is listed in the compatibility guide. There is no official Libre app for Android smartwatches.
With the Libre Watch app:
- View glucose readings on your watch.
- Receive alarms on your watch.
- Important: Don’t use the Watch app for therapy decisions – your phone app is always the source of truth.
Lot Checker: Recall Before Insertion
Every serial number should be checked before inserting:
- Falsely low readings (Libre 3 & 3 Plus): freestylecheck.com
- Falsely high readings (Libre 3 Plus only): freestyleconfirm.com
Where the serial number is: on the back of the applicator or packaging. If your sensor is already inserted, find it in the Libre app under Info > Last 3 Sensors or in the reader under Gear icon > System Status > System Info.
Sources
- Abbott, FAQ “Smartphone Compatibility Check” (iOS 16.0, Android 11, Libre app replaces FreeStyle Libre 3 app), retrieved 25.10.2026: freestylelibre.de
- Abbott, FAQ “Switch to Libre App” (active sensor cannot be transferred, report data transfers), retrieved 25.10.2026: freestylelibre.de
- Abbott UK, FAQ “I started a FreeStyle Libre 3 Sensor but lost or need to replace my smartphone…” (with LibreView account the sensor can keep being used, without one a new sensor is needed), retrieved 25.10.2026: freestyle.abbott/uk-en
- Abbott UK, FAQ “What happens if I lose or change my phone?” (history available in LibreView), retrieved 25.10.2026: freestyle.abbott/uk-en
- Abbott, FAQ “Signal Loss Alarm” (20 minutes, sensor too far away, Bluetooth issues), retrieved 25.10.2026: freestylelibre.de
- Abbott, Libre App (Watch app Apple Watch only), retrieved 25.10.2026: freestylelibre.de
- Abbott, FreeStyle Libre 3 App (iOS and Android compatibility), retrieved 25.10.2026: freestylelibre.de
- Lot checker falsely low (freestylecheck.com), retrieved 25.10.2026: freestylecheck.com
- Lot checker falsely high (freestyleconfirm.com), retrieved 25.10.2026: freestyleconfirm.com
- FDA, Glucose Monitor Sensor Recall (Libre 3 & 3 Plus), retrieved 25.10.2026: fda.gov
- BfArM, Customer Information 55464/25 (falsely low readings), retrieved 25.10.2026: bfarm.de
Not affiliated with Abbott. “FreeStyle”, “Libre” and related brand names are trademarks of Abbott. Not medical advice: questions about therapy belong with your diabetes team. Last updated: October 25, 2026.