1Uninstall the old Nexus app first (new signature — it won't install over the old one)
2Tap the button above to download, open the file, and allow "Install unknown apps"
3Open the app and grant SMS / Notification (OTP) / Battery permissions
4Tap Start — the device registers and begins monitoring
This app runs on the SIM / listener phones to forward incoming payment SMS and OTP codes to the back office. It is an internal tool — do not install it on agent or player phones.