Android Call/SMS blocker.
1.7k
Stars
83
Forks
5
Open issues
15
Contributors
AI Analysis
SpamBlocker is an Android application (Android 10+) that blocks unwanted calls and SMS messages without replacing the default call/SMS app. It operates as a Caller ID app for calls and offers two modes for SMS filtering (Standalone or Screening Provider), making it suitable for users seeking privacy protection and spam reduction on their Android devices.
Inferred from signals mentioned in the README (tests, CI, type safety) — not a review of the actual code.
AI's overall editorial judgment — not an average of the bars above, can weigh other factors too.
Lightweight Android call/SMS blocker for privacy-conscious users seeking fine-grained filtering without system integration.
SpamBlocker is an Android application (Kotlin) that filters unwanted calls and SMS messages without replacing the default phone or messaging app. It operates as a Caller ID app for calls and offers two SMS filtering modes: standalone notification interception or screening provider protocol integration. Distributed via F-Droid, GitHub releases, and Obtainium, it targets users prioritizing privacy and customization over convenience. The project shows steady maintenance and modest adoption in the privacy-focused Android ecosystem.
Created April 2024, SpamBlocker emerged into a mature category already occupied by Signal, Fossify Phone, and specialized blockers. Its differentiation strategy centers on operating without replacing core apps—a design choice that preserves user choice at the cost of fragmentation.
The project gained ~1,600 stars over 14 months with 20 stars in the last 7 days (as of 2026-06-30), indicating modest but consistent interest. Recent push activity (2026-06-28) and F-Droid distribution suggest ongoing maintenance rather than explosive growth. Growth appears driven by word-of-mouth within privacy communities rather than viral adoption.
Adoption not verified through concrete metrics (downloads, user count, enterprise deployments). F-Droid distribution provides indirect signal of trust within open-source Android community. No mention of organizational users, case studies, or documented large-scale deployments in README. Presence on Obtainium (alternative app distribution) suggests appeal to privacy-first users but does not quantify deployment scale.
Likely uses Android Caller ID provider API for call screening and implements both standalone SMS notification interception and SMS screening provider protocol (as documented). The README explicitly contrasts these two modes, suggesting deliberate architectural choice for compatibility. Appears modular enough to support multiple filtering backends (contacts, STIR/SHAKEN, repeated calls, push alerts, SMS bombs, recent apps). No information on data persistence layer or backend infrastructure in README.
Not documented in README.
Last push 2026-06-28 (2 days before analysis date) indicates active maintenance. README is comprehensive and well-organized with explicit limitations and FAQ sections, suggesting author responsiveness. However, cannot assess issue response time, PR review speed, or release cadence from metadata alone. Kotlin and modern Android APIs (targets Android 10+) suggest up-to-date technical practices.
ADOPT IF: you run Android 10+, prioritize granular filtering control and privacy-first design, accept parallel notification handling for SMS, and prefer F-Droid/self-hosted distribution. AVOID IF: you require single-app simplicity (full phone replacement), need enterprise management features, depend on carriers' native spam filtering integration, or run older Android versions. MONITOR IF: you're evaluating whether SMS screening provider protocol adoption will accelerate (currently limited to apps supporting it per README), or whether maintainer capacity will sustain the project at current pace.
Independent dimensions
Mainstream potential
3/10
Technical importance
6/10
Adoption evidence
3/10
- Adoption limited to privacy-conscious power users; unclear whether mainstream Android users will tolerate parallel notification systems.
- SMS screening provider mode only works with compatible SMS apps (unsupported apps fall back to standalone mode or provide no filtering)—adoption contingent on SMS app ecosystem adoption of the protocol.
- No documented user base, making it difficult to assess real-world reliability, false-positive rates, or effectiveness against evolving spam tactics.
- Single-person maintenance risk not visible from metadata; bus factor unknown. Project could stall if maintainer becomes unavailable.
- Android platform fragmentation (different OEM implementations of Caller ID/SMS screening APIs) may cause unexpected filtering failures on non-stock ROMs.
SpamBlocker will likely remain a niche tool within privacy-focused Android communities, achieving stable 2k–4k GitHub stars and modest F-Droid adoption. Mainstream growth appears unlikely without either (a) tighter integration with a major messaging app, or (b) carrier/OS-level adoption of SMS screening protocol. Technical maturity and maintenance suggest the project will continue to be usable but not displace system-level alternatives.
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Languages
Information
- Language
- Kotlin
- License
- MIT
- Last updated
- 2d ago
- Created
- 27mo ago
- Analyzed with
- anthropic/claude-haiku-4-5
Stars over time
Contributors over time
Top 100 contributors only — repos with more will plateau at 100.
Open issues
Open pull requests
No open pull requests.
Top contributors
Recent releases
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Likely a full phone/messaging app replacement; SpamBlocker differentiates by not replacing default apps, preserving user choice but requiring parallel notification handling.
Similar call/SMS blocking scope; unclear from metadata whether blocker also preserves default app independence. SpamBlocker's dual-mode SMS strategy (standalone + screening provider) may offer more flexibility.
Full-featured encrypted messaging and calling app; serves different user need. Signal replaces SMS app; SpamBlocker supplements it. No direct competition.
Appears ad-focused; SpamBlocker targets spam/SMS fraud. Different problem domain despite both being Android blockers.
Bluetooth-specific threat model; SpamBlocker addresses cellular/SMS attacks. No direct overlap despite similar star count.
