Freestyle Libre 1
To use your Libre as a CGM that is getting new BG values every 5 minutes you first need to buy a NFC to Bluetooth adapter like:
MiaoMiao Reader (version 1 or 2) https://www.miaomiao.cool/
Blucon Nightrider https://www.ambrosiasys.com/our-products/blucon/
Bubble https://bubbleshop.eu/ or for Russian users https://vk.com/saharmonitor/
Additionally it is possible to use a specific watch, the Sony Smartwatch 3 which has an NFC chip which can be enabled and can be used as a NFC collector. However the custom NFC to Bluetooth adapters listed above offer a less complex solution and would be used by the majority of those wanting to use their Libre 1 as a CGM.
Sony Smartwatch 3 (SWR50) https://github.com/pimpimmi/LibreAlarm/wiki/
As it currently stands, if using Libre 1 as BG source you cannot activate ‘Enable SMB always’ and ‘Enable SMB after carbs’ within the SMB algorithm. The BG values of Libre 1 are not smooth enough to use it safely. See Smoothing blood glucose data for more details.
If using xDrip+
If not already set up then download xDrip+ and follow instructions on LimiTTEer or Libre Alarm.
In xDrip+ go to Settings > Interapp Compatibility > Broadcast Data Locally and select ON.
In xDrip+ go to Settings > Interapp Compatibility > Accept Treatments and select OFF.
If you want to be able to use AndroidAPS to calibrate then in xDrip+ go to Settings > Interapp Compatibility > Accept Calibrations and select ON. You may also want to review the options in Settings > Less Common Settings > Advanced Calibration Settings.
Select xDrip+ in ConfigBuilder (setting in AndroidAPS).
For settings in xDrip+ with screenshots see xDrip+ settings page. There is a part for basic xDrip+ settings and for Freestyle Libre xDrip+ settings.
If AAPS does not receive BG values when phone is in airplane mode, use ‘Identify receiver’ as describe on xDrip+ settings page.
If using Glimp
You will need Glimp version 4.15.57 or newer. Older versions are not supported.
If not already set up then download Glimp and follow instructions on Nightscout.
Select Glimp in ConfigBuilder (setting in AndroidAPS).