here's one way to know

Google Play | *This app requires root access and will only run on devices with Qualcomm chipset.*

 

SnoopSnitch collects and analyzes mobile radio data to make you aware of your mobile network security and to warn you about threats like fake base stations (IMSI catchers), user tracking, and SS7 attacks.

To use SnoopSnitch, a rooted device with a Qualcomm chipset running stock Android 4.1 or higher is required. Unfortunately, custom ROMs are often unsupported at the moment as they can lack necessary proprietary drivers. (Some successful CyanogenMod installs have been reported.)

This application uses data contributed by other users. By choosing to upload your measurement results or security events, you can help improve this data base and support future research.