Title: Filtr: A New Privacy Solution That Neutralizes Ads Across iPhone and Mac Applications

Ad blockers are widely recognized as essential tools for enhancing security and privacy, with even the FBI advocating for their use to mitigate online threats. While these utilities significantly improve the browsing experience, they traditionally fail to stop the pervasive tracking embedded within third-party applications. However, a new capability introduced in iOS 26 and macOS 26 has enabled the creation of the first device-level ad blocker that functions universally across Apple’s ecosystem, including iPhones, iPads, and Macs, extending protection beyond the web browser.

Filtr is a paid feature integrated into Wipr, a popular Safari ad blocker developed by Kaylee Serena Calderolla. Wipr is designed to prevent advertisements from loading in Safari entirely, thereby blocking the tracking codes advertisers use to monitor user activity across the web. This ensures a browsing environment free from advertiser surveillance. Filtr expands on this functionality by utilizing a new Apple technology known as "URL filters." This feature allows developers to block access to specific domains or websites at the network level, rather than restricting them solely within a browser interface.

As a long-time paying customer of Wipr, I have relied on it for years to protect my Apple devices. My privacy setup also includes ad blockers for non-Safari browsers on desktops and a Pi-hole server on my home Wi-Fi network. While effective, these solutions leave my devices vulnerable to ads when connected to external networks or when using applications saturated with advertisements, including non-Safari browsers. Consequently, I was eager to test Filtr.

Calderolla emphasized that her applications do not collect personal data, a feature that aligns with the privacy-preserving nature of Apple’s URL filter implementation. With no trade-offs and immediate benefits, I subscribed to the $5 annual plan and enabled the URL filter on my iPhone. The results were instant: applications opened without the usual influx of advertisements, leaving only greyed-out placeholders where ads would have appeared.

Calderolla noted that Filtr is currently the only application to leverage the URL filters feature, a situation partly due to the technical complexity of its implementation. In a May blog post, she described the development process as a "nightmare," citing sparse documentation from Apple that required significant independent research to understand how to properly implement the feature.

The tool operates using a blocklist maintained by Calderolla. Filtr employs a "pre-filter" list stored locally on the user’s device, which is updated automatically via the Wipr app. This local list allows most websites to load normally. However, if the pre-filter identifies a potential match with the blocklist, it verifies the domain against Calderolla’s servers. To protect user privacy, these verification requests are routed through Apple’s servers as a proxy, ensuring that app developers cannot identify who is querying their blocklists. This setup allows users to configure Filtr once and maintain it with minimal effort.

While no ad blocker is flawless, Filtr represents a significant victory for privacy by minimizing exposure to ad networks. There are some limitations, though they are not dealbreakers. Notably, Filtr does not block ads that a...

Source: TechCrunch Generated at: 2026-06-04 21:44:09 UTC