Callfilter.app vs Should I Answer?

Callfilter.app is an Android app that blocks incoming calls according to rules set by the user. It can reject 8-digit numbers, numbers on a personal list, custom-pattern matches, or all incoming calls. Custom matching supports regular expressions, and users can choose to receive a notification when a call is rejected. CallFilter checks calls on the device through Android’s CallScreeningService API, using a local SQLite-based rule engine without remote database lookups. The maker describes it as offline, with no accounts or tracking. Its privacy policy says the app does not send personal data to external servers and does not use third-party SDKs, advertising networks, or tracking libraries. The app is free and open source, and the maker invites users to audit or contribute to the project on GitHub. It filters calls according to the user’s settings; it does not replace the phone app. The Play Store listing warns that some features may not work correctly on Samsung devices running Android 12 or later.

Should I Answer? is a community-based service and mobile app for identifying and guarding against unwanted calls, telemarketing, and expensive outgoing calls. Its database combines community reviews with phone number ratings and is refreshed daily. On Android, the app can check a locally stored database without an internet connection and can optionally block unwanted calls automatically. The maker warns that automatic blocking may not work on every phone model. On iOS, number ratings appear in CallerID during calls or in Call History through the call blocking and identification extension. The service is also available on the web and as an extension. The Android app requires Android 4.1 or higher; Android 6 and newer require permissions for contacts, call information, and drawing over other apps. The Android manual says the local database stores phone numbers and statistics, while user reviews can be downloaded from the web service. The Android plan is free. An iOS automatic database updates plan has no listed price and includes a one-month trial period and free phone number information search.