Description:
My Call Filter is a simple and efficient application to help you control incoming calls, blocking unwanted numbers locally, transparently, and without collecting personal data.
The app acts as a system call filter, without interfering with the standard Android phone application and without replacing existing native blocking mechanisms.
Main features:
1) Blocking by custom lists.
2) Blocking by area code and prefixes: Allows you to filter calls based on area codes and prefixes, helping to reduce calls that use area code or prefix spoofing.
Privacy:
1) No collection of personal data;
2) No information sent to external servers;
3) All processing is done locally on the device; and
4) The application does not access or store call recordings, conversation content, or sensitive data.
Important Notes:
1) The app does not promise to automatically identify scams or fraud or identify the real number of a call with simulated numbering (spoofing). Blocking by area code and prefixes only helps reduce calls with simulated numbering, with blocking rules defined by the user themselves, by identifying repeated numbers with identical prefixes in their smartphone's call logs.
2) To stop filtering calls, simply uninstall the application or remove it from your Android settings as a call filter.
About the development:
This application was developed with the support of artificial intelligence tools, including ChatGPT, used to assist in development and documentation.
Brief educational description of area spoofing by ChatGPT:
"Area spoofing is a technique in which the number displayed on the call does not correspond to the actual originating number.
A common pattern is the use of the same area code and prefix as the recipient, with random changes to the final digits with each new call. This creates the appearance of a local or known call, increasing the chance of being answered.
This type of variation is used to make it more difficult for operators or the user themselves to block calls, which are usually based on individual numbers.
In simplified terms, calls with simulated numbering can occur when automated telephony systems (such as dialing platforms or VoIP services) allow the caller ID to be configured.
In these systems, it is possible to:
- Manually define the area code and prefix displayed;
- Change the final digits of the number with each call;
- Generate large volumes of calls with different numbers, but with a similar appearance."