Filtr launches as a device-level ad blocker for Apple devices

A new privacy tool called Filtr has launched as a device-level ad blocker that works across iPhones, iPads, and Macs. Developed by Kaylee Serena Calderolla, the application is the first so far to utilize the new URL filters feature introduced in iOS 26 and macOS 26, according to Calderolla. URL filters are a feature in iOS 26 and macOS 26 that allows developers to block access to websites at the network level, rather than restricting ad blocking solely to web browsers. By utilizing this native system capability provided by Apple, Filtr can block advertisements inside other applications on a user’s device. Unlike traditional browser extensions that only operate within Safari, this network-level approach allows the software to intercept and block ad-server requests across the entire operating system.

Calderolla, who is also the developer of Wipr—a Safari browser ad blocker that bundles Filtr—described the process of implementing the URL filters feature as a “nightmare” in a blog post published in May. She noted that Apple’s documentation on the feature was sparse, which required significant development effort to understand how to deploy it. Despite these implementation challenges, Calderolla stated that Filtr apps “do not collect personal data.” The app operates by consulting a pre-filter blocklist stored directly on the user’s device, which is used to determine if a website should be blocked. This local pre-filter list allows the app to evaluate web requests directly on the device, supporting the developer’s claim regarding data privacy.

Wipr, the Safari browser ad blocker that bundles Filtr, is available for $5 in the Apple App Store. While Wipr handles browser-level blocking, Filtr requires an additional purchase to enable system-wide blocking across other apps. Users can choose between two pricing options:

• A $5 annual subscription
• A $25 for a one-time lifetime payment

However, the ad blocker has limitations. Filtr does not always block ads served directly from the websites visited, such as those loaded within the Facebook or Reddit apps. Because blocking these direct-domain ads could break the functionality of the applications entirely, the tool’s effectiveness varies depending on how the advertisements are delivered.

Why it matters

Filtr represents a shift in ad-blocking capabilities by leveraging native Apple features to extend protection beyond the browser and into the app ecosystem, though effectiveness varies by ad source.