The icon and the connection are different kinds of evidence
A phone can show a 5G badge while using a 4G anchor connection, depending on the carrier, handset and network mode. TrueG was built to make the underlying radio state easier to inspect without requiring root access or a user account.
The app has a native Kotlin module that reads Android telephony information and reports a small set of states to its React Native interface: 4G, 5G non-standalone, 5G standalone, 3G and unknown. A persistent notification makes the current result glanceable.
A native module bridges platform APIs into the app
The JavaScript detector calls a React Native native module rather than guessing from the status-bar icon. The Android implementation uses TelephonyManager listeners and callbacks, including display-information overrides, and maintains the latest values used for network-mode classification.
The repository separates the platform detector from the React Native screen and includes tests for the detector, permission handling, storage, app behavior and network-status hook. The mobile interface can present the result while the platform service listens for changes.
Device and carrier behavior still matters
Android exposes different telephony signals across API levels and handset vendors. Permissions may be required, some fields may be unavailable, and a carrier can use a network configuration that complicates the distinction. TrueG should be treated as a device diagnostic, not a universal guarantee that every carrier’s icon is wrong.
The useful engineering lesson is to query the source that best represents the system state, preserve an unknown result when evidence is missing, and explain the limits of the data. A good diagnostic tool is allowed to say “unknown.”
INSPECT THE IMPLEMENTATION
Read the code and project notes
The details above describe the public repository and project status as reviewed for this portfolio. Follow the source to inspect the implementation, setup instructions and current limitations.
TrueG native telephony module and detector
