PhoneBlock

PhoneBlock is a free, community-driven call-blocking service for Android, landlines and phone systems. It is strongest for people who want to draw on a shared spam database without a subscription; iPhone users get a contact-sync workaround rather than a native app, and business use is discouraged.

Its combination of community reporting and several connection methods is compelling, particularly for Android and landline users. The main trade-offs are the less direct iPhone setup and the operator’s warning against commercial use.

Overview

PhoneBlock uses a shared database of reported spam numbers to identify unwanted calls. Users can contribute reports through the app, website or personal blacklist, so a number reported by one person can help inform protection for others. This community approach is useful beyond maintaining a private blocklist, though its reach depends on contributions from users.

The software is licensed under GPL-3.0 and run as a private project by Bernhard Haumacher. The site says it has no ads or third-party trackers. Its privacy policy says unregistered visitors’ IP addresses are logged temporarily for error analysis and deleted after 14 days.

Key features

Android blocking and privacy

The Android app blocks known spam calls, keeps a call history and supports spam reports and personal lists. It requires Android 10 or later, ruling it out for older devices. For incoming calls, it sends only the phone number’s SHA-1 hash and does not access contacts, a meaningful privacy advantage for people who do not want a call-blocking app reading their address book.

Landline and phone-system connections

Landline users can choose a router dongle, a cloud answering machine through Fritz!Box or a blocklist phonebook synced by CardDAV. Phone systems can download the blocklist in various formats or query it through an API, and the integration page links to a community 3CX project. This breadth makes PhoneBlock more adaptable than an app-only blocker, but it does mean the best route depends on the equipment and setup a household or system already uses.

iPhone through CardDAV

The documented iPhone method syncs spam numbers into contacts through CardDAV. A native iPhone app is in development, with beta registration offered. For now, iPhone users must accept a contact-based setup rather than the direct app experience Android users get.

Answering machine and support

When the answering machine is used, PhoneBlock stores the Fritz!Box IP address for registration and compares incoming caller numbers against its spam database. The operator offers email help, including for users whose number has been mistakenly added to the blocklist.

Pricing

PhoneBlock is free to use, with donations optional. Its PhoneBlock plan costs nothing. There is no free trial because the service is already free; there are no paid tiers or subscription terms to weigh against its core offering.

The free model suits people who want shared spam blocking without a recurring charge. The important limit is not a usage quota but the terms: PhoneBlock advises against business use and places responsibility for resulting damage on the user. Organizations seeking a service explicitly intended for commercial deployment should choose another option.

Platforms

PhoneBlock supports Android, iOS, web, API and self-hosted use. Android requires version 10 or later. On iPhone, the documented CardDAV contact sync is the available method, while a native app remains in development. Landline access includes the router dongle, Fritz!Box cloud answering machine and CardDAV phonebook approaches; phone systems can use downloads or the API.

Who it's for

PhoneBlock is a good fit for Android users on version 10 or later who want caller screening and community reporting without paying, and for landline users willing to connect it through one of the supported methods. It also suits technically capable phone-system users who want to download or query a shared blocklist. iPhone users can use it, but should be comfortable syncing numbers through CardDAV. Businesses should heed the operator’s explicit advice against business use.

Pros and cons

• Pro: Community reports feed a shared blacklist, extending protection beyond each user’s personal list.
• Pro: Free use with optional donations avoids a recurring subscription.
• Pro: Android’s incoming-call handling sends only a SHA-1 hash and does not access contacts.
• Pro: Router, Fritz!Box, CardDAV and API options cover more than smartphone-only use.
• Con: The Android app requires Android 10 or later, excluding older devices.
• Con: The documented iPhone route syncs numbers into contacts; a native app is still in development.
• Con: The terms advise against business use and assign users responsibility for resulting damage.

Alternatives

For a broader comparison, see Spam Call Blocking Apps.

• Getcontact is worth considering if you want a freemium Android, iOS or web option with a paid Premium plan at $2.99 a month; its free basic version costs nothing.
• YouMail may suit readers who want cloud voicemail features alongside blocking: its free plan includes 50 cloud messages, 100 voicemail-to-text transcriptions per month and unlimited known-spammer blocking.
• Hiya Spam Blocker offers a free basic plan with caller ID, basic call blocking and spam reporting on Android and iOS, plus a free trial.
• NumBuster is another freemium choice for Android, iOS and web users who want a free mobile app and the option of paid features.
• RoboKiller offers a free plan with a global blacklist, spam-call notifications, weekly insights, spam reporting and Spam Patrol, as well as a free trial.
• Should I Answer? may fit Android users seeking free community-based call protection; it also supports iOS, web and an extension.
• Who Called is a free, open-source alternative for Android, iOS and web users who want a service with no paid tiers stated.
• Whoscall provides a free Android and iOS plan with caller ID, call blocking, number, URL and screenshot checks, and scam reports and rewards.

Verdict

Choose PhoneBlock if you want free, community-based spam blocking and need more than a standalone mobile app—especially on Android, a landline or a phone system. Its shared blacklist, open-source licence and multiple connection methods are the strongest reasons to pick it. Look elsewhere if you need a native iPhone app now or a service intended for business use.