When loading it for the first time, the My myETraining / Upgrado app requires access to your phone localization services.
The requirement is tied to the fact that the OS (Android) does not allow Bluetooth access without it, and without Bluetooth the myETraining / Upgrado app cannot connect to your home trainer.
Though it might seem like an unusual request, it really isn't - the Bluetooth connection might be used by the app to locate your phone.
For instance: if while scanning for the home trainer the app registers the location of Bluetooth transmitters, the app itself confirms that the phone is around a specific location and thus localizes the user.
This explains why the OS requires the user permission to track the position of the phone.
You can find an explanation for this on the Android website at this link: https://developer.android.com/guide/topics/connectivity/bluetooth
(Here's an extract indicating the need for an app using Bluetooth to also require localization permission).
Note: Should the user not consent to localization, the myETraining / Upgrado app won't be able to connect to the home trainer via Bluetooth.
The most recent version can also limit the localization access only when effectively using the app. This type of limited access is enough to properly use the myETraining o app to work out.
The myE-Training app locates position of the device only when the "Record GPS Course" function is active.
All the other functions on the myE-Training app do not locate the device position.
Conversely, the MyRealVideo app registers the GPS position of the device along the whole course as it needs to record both speed and position while filming the video.
Lastly, the Upgrado app never locates the position of the device.