RMS - Caller ID service analyzes recent call history using call history access rights and displays caller information to the user in real time when receiving a call. It can identify spam and advertising calls, and repeatedly emphasizes that the caller ID service is the core function of the app.

Main functions:
- When a call comes in, caller information is displayed as a pop-up (overlay) at the top of the screen
- Check recent call history (caller, number, time, type) within the app
- Identification and guidance of spam/advertisement calls
- The collected information is not transmitted externally to protect personal information, and is immediately destroyed when the app is deleted.

Permission information:
- This app requests only call history access rights (READ_CALL_LOG) in accordance with Google Play policy, and does not use it for any purpose other than providing the caller ID service.
- Text transmission rights (SEND_SMS) are not used.

The "caller ID service" is clearly indicated in all places, including the app name, description, permission information, and privacy policy.