I need an Android application that can place voice calls while letting me choose the caller ID the other party sees. The basic flow is straightforward: open the app, enter the number I want to display, enter (or select) the number I’m actually calling, then tap Call. Whoever answers should see the caller ID I supplied, not my device’s real one. Any reliable technical path is acceptable—direct SIP integration, Twilio, Nexmo, or another compliant gateway—as long as it works on recent Android versions and across international routes. I don’t need messaging, contact management, or sign-in screens unless they are strictly required to support the calling feature. Deliverables • Android Studio project (Java or Kotlin) ready for build and future updates • Signed APK that runs on Android 10 and above • Clear setup guide covering API keys, SIP credentials, or other configuration steps • Brief note on any third-party costs, limits, or regulatory considerations tied to your chosen solution Acceptance test: I install the APK, place sample calls to domestic and international numbers, and the recipient consistently sees the caller ID I entered. When you respond, outline the API or gateway you plan to use, how you’ll handle call routing, and any legal or carrier restrictions I should be aware of.