Call Blocker - Block Numbers positions itself as a frontline defense against the growing epidemic of spam calls and telemarketing intrusions on Android devices. Developed by Spam Call Blocker Apps, this solution leverages community-reported data and automated filtering to identify potentially unwanted calls before they reach the user's device. The app operates within the competitive call-blocking market by focusing on simplicity and effectiveness rather than complex feature sets. The core functionality centers around three primary mechanisms: automatic spam detection using a continuously updated database, user-configurable blacklisting for specific numbers, and whitelisting capabilities for important contacts. The system automatically screens incoming calls against known spam databases, providing real-time warnings or outright blocking based on user preferences. Users can manually add numbers to their personal block list, create custom blocking rules based on number patterns, and review blocked call logs with timestamps and geographic information. User experience demonstrates thoughtful design with an intuitive interface that prioritizes essential functions. The main dashboard provides immediate access to blocking statistics, recent activity, and settings. Real-world usage patterns show most users configure the app to automatically block all suspected spam while allowing contacts and recently dialed numbers through. The notification system alerts users to blocked calls without interrupting current activities, though some legitimate calls may occasionally be caught in the filter. User feedback trends indicate generally positive experiences with specific praise for effectiveness. Katy Ford's July 2025 review notes reliable contact-only filtering despite occasional over-blocking, while Sara W.'s June 2025 endorsement highlights exceptional performance against persistent telemarketing calls where paid alternatives failed. Multiple reviews from Mr. Clay K in June 2025 commend the developers' responsiveness to user feedback and subsequent feature improvements, suggesting active maintenance and customer engagement. The application demonstrates notable strengths in spam detection accuracy and operational simplicity, though limitations include potential false positives with legitimate calls and advertising presence in the free version. Ideal use cases involve users experiencing high volumes of unwanted calls who prioritize automated protection over granular control. The solution proves particularly valuable for individuals receiving frequent telemarketing calls or those seeking hands-off operation after initial configuration.