Supporting Reduced User-Agent and Client Hints

In 2022, Google, the dominant web browser Chrome maker, started testing the so-called Reduced User Agent.

These changes, combined with the adoption of Client Hints, require additional handling of these hints.

As of December 2022, Wide Angle Analytics has implemented support for Client Hints. With this feature, we support the existing User-Agent standard and upcoming reduced/Client-Hints implementation.

Supporting Client Hints

Wide Angle Analytics processes following Client Hints:

  • sec-ch-ua - Browser name with major version
  • sec-ch-ua-mobile - Whether the browser prefers to be treated as a mobile device
  • sec-ch-ua-platform - An operating system without version information.

If Client Hints are provided, Wide Angle Analytics will prioritize these over the legacy User-Agent header.

When Client Hints are absent or malformed, service will fall back onto the old header.

Impact of Client Hints

Even core Client Hints allow Wide Angle Analytics to report which browser and operating system the visitor used. The most significant impact is in device detection.

Rather than requesting via additional browser directive, the Sec-CH-UA-Model, and hoping to be provided with relevant information if allowed, we opted for a privacy-first approach.

This limits the granularity of mobile device types detected.

For Client Hints enabled browser, we only distinguish four types of devices:

  • Desktop, which covers workstations, desktops and laptops,
  • Mobile, which covers smartphones, tablets and smartwatches,
  • Bot, which covers various bots and crawlers,
  • and lastly, the Unknown type, a fall back for other unrecognized types.

Example

Here is a practical, real-life example of how Wide Angle Analytics parses client hints.

sec-ch-ua: "Google Chrome";v="107", "Chromium";v="107", "Not=A?Brand";v="24"
sec-ch-ua-mobile: ?1
sec-ch-ua-platform: "Android"
User-Agent: Mozilla/5.0 (Linux; Android 10; SM-G981B) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.162 Mobile Safari/537.36
Reporting of visitor device based on Client Hints

The above visit will be reported as a visitor running Android and surfing using Chrome Browser. It will be tagged as a generic mobile device.