Corta Spam review
A rule-heavy, on-device Android blocker for precise call screening before ringing.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
Corta Spam is an open-source Android app for screening incoming calls before the phone rings. It suits people who want detailed local control over unwanted calls rather than a system based on community reports. Rules can use manual blocklists and allowlists, prefixes, suffixes, wildcards, country codes, repeat-caller attempt thresholds, and quiet-hours schedules. The app also includes caller identification on the call screen and a bundled on-device spam list.
Its standout strength is the depth of its rule engine. Corta Spam can block or allow calls according to several types of number and caller behavior, giving users more control than a simple blocklist. It also includes an experimental auto-responder with a custom greeting, plus call logs, statistics, and JSON backup and restore. The open-source design, ad-free and tracker-free positioning, and on-device data handling make it a focused option for users who prefer local processing and configurable policies.
Platform fit is the main boundary. Android is the usable platform for call blocking, while the iOS shell can build and run but does not yet provide iOS call blocking. The app also lacks community reports, so it is less suited to people who want crowdsourced identification of known nuisance numbers. Choose Corta Spam for Android-based, rule-heavy screening with local controls; consider an alternative if iOS support or community-powered spam intelligence is central to the buying decision.
Corta Spam pros and cons
- Where it wins
- Screens calls before the phone rings using detailed local rules
- Supports country, wildcard, repeat-caller, quiet-hours, and list controls
- Open-source, ad-free, tracker-free, and designed for on-device data handling
- Where it doesn't
- Android is the usable platform for call blocking
- Does not include community spam reports
- Auto-responder functionality is experimental
Corta Spam fact sheet, pricing and score →
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