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Articles on user agent strings and device detection from useragent.in.
Anatomy of a User Agent String
Anatomy of a User Agent String. A practical look at user agent string — decoding each token in order.
Why Every Browser Still Claims to Be Mozilla
Why Every Browser Still Claims to Be Mozilla. A practical look at Mozilla token — the historical accident behind the prefix.
Chrome User Agent Format Explained
Chrome User Agent Format Explained. A practical look at Chrome user agent — reading a modern Chrome string.
Safari and WebKit User Agents
Safari and WebKit User Agents. A practical look at Safari user agent — how Apple builds its strings.
Firefox User Agent Structure
Firefox User Agent Structure. A practical look at Firefox user agent — Gecko tokens and versioning.
Edge User Agents After the Chromium Switch
Edge User Agents After the Chromium Switch. A practical look at Edge user agent — what changed and why.
Mobile Versus Desktop User Agents
Mobile Versus Desktop User Agents. A practical look at mobile user agent — the tokens that signal a phone.
Android User Agent Variations by Vendor
Android User Agent Variations by Vendor. A practical look at Android user agent — device strings across manufacturers.
iOS User Agents and Version Freezing
iOS User Agents and Version Freezing. A practical look at iOS user agent — why versions stopped moving.
Tablet Detection From the User Agent
Tablet Detection From the User Agent. A practical look at tablet detection — separating tablets from phones.
Smart TV and Console User Agents
Smart TV and Console User Agents. A practical look at smart TV user agent — strings from living-room devices.
Wearable Device User Agents
Wearable Device User Agents. A practical look at wearable user agent — what watches report.
Bot and Crawler User Agents Worth Knowing
Bot and Crawler User Agents Worth Knowing. A practical look at crawler user agent — identifying legitimate crawlers.
Googlebot User Agent Strings in Detail
Googlebot User Agent Strings in Detail. A practical look at Googlebot user agent — desktop and smartphone variants.
Bingbot and Other Search Crawlers
Bingbot and Other Search Crawlers. A practical look at Bingbot — strings from major search engines.
AI Crawlers: GPTBot, ClaudeBot and Others
AI Crawlers: GPTBot, ClaudeBot and Others. A practical look at AI crawler — the newest category of agents.
SEO Tool Crawlers and Their Signatures
SEO Tool Crawlers and Their Signatures. A practical look at SEO crawler — strings from auditing services.
Uptime Monitors and Their User Agents
Uptime Monitors and Their User Agents. A practical look at uptime monitor — automated availability checks.
HTTP Client User Agents: curl, wget and More
HTTP Client User Agents: curl, wget and More. A practical look at curl user agent — command line and library defaults.
Python Requests and Library Defaults
Python Requests and Library Defaults. A practical look at Python requests — what SDKs send by default.
In-App Browser User Agents
In-App Browser User Agents. A practical look at in-app browser — strings from embedded webviews.
Facebook and Instagram Webview Detection
Facebook and Instagram Webview Detection. A practical look at webview detection — identifying social in-app browsers.
User Agent Client Hints: The Modern Approach
User Agent Client Hints: The Modern Approach. A practical look at client hints — structured replacement for the string.
Sec-CH-UA Headers Explained
Sec-CH-UA Headers Explained. A practical look at Sec-CH-UA — reading the new hint headers.
High Entropy Client Hints and Permissions
High Entropy Client Hints and Permissions. A practical look at high entropy hints — requesting detailed device data.
User Agent Reduction in Chrome
User Agent Reduction in Chrome. A practical look at UA reduction — why the string is getting shorter.
Parsing User Agents Reliably
Parsing User Agents Reliably. A practical look at user agent parsing — building a robust parser.
Regex Pitfalls in User Agent Detection
Regex Pitfalls in User Agent Detection. A practical look at user agent regex — patterns that break over time.
Why Feature Detection Beats User Agent Sniffing
Why Feature Detection Beats User Agent Sniffing. A practical look at feature detection — testing capability not identity.
User Agent Spoofing: Methods and Motives
User Agent Spoofing: Methods and Motives. A practical look at user agent spoofing — why and how strings get changed.
Changing Your User Agent in Each Major Browser
Changing Your User Agent in Each Major Browser. A practical look at change user agent — practical configuration steps.
Developer Tools Device Emulation
Developer Tools Device Emulation. A practical look at device emulation — testing across simulated devices.
Detecting Fake User Agents
Detecting Fake User Agents. A practical look at fake user agent — spotting inconsistent claims.
User Agents and Analytics Accuracy
User Agents and Analytics Accuracy. A practical look at analytics accuracy — how misparsing skews reports.
Server Logs and User Agent Analysis
Server Logs and User Agent Analysis. A practical look at log analysis — extracting insight from raw logs.
Blocking Bots by User Agent: Why It Fails
Blocking Bots by User Agent: Why It Fails. A practical look at bot blocking — the weakness of string-based rules.
robots.txt and Crawler User Agents
robots.txt and Crawler User Agents. A practical look at robots.txt — matching directives to agents.
User Agents in Content Negotiation
User Agents in Content Negotiation. A practical look at content negotiation — serving variants by client.
Legacy Browser User Agents
Legacy Browser User Agents. A practical look at legacy browser — strings from older clients.
Internet Explorer User Agent Quirks
Internet Explorer User Agent Quirks. A practical look at Internet Explorer — compatibility tokens explained.
Opera User Agent History
Opera User Agent History. A practical look at Opera user agent — from Presto to Chromium.
Samsung Internet and Vendor Browsers
Samsung Internet and Vendor Browsers. A practical look at Samsung Internet — OEM browser identification.
Gaming Console Browsers
Gaming Console Browsers. A practical look at console browser — PlayStation and Xbox strings.
E-Reader and Kiosk User Agents
E-Reader and Kiosk User Agents. A practical look at e-reader user agent — niche device identification.
User Agents and Accessibility Tools
User Agents and Accessibility Tools. A practical look at accessibility tools — assistive technology signals.
Privacy Implications of the User Agent
Privacy Implications of the User Agent. A practical look at user agent privacy — identification through the string.
User Agent Entropy and Fingerprinting
User Agent Entropy and Fingerprinting. A practical look at user agent entropy — how much the string reveals.
Testing Your Own User Agent
Testing Your Own User Agent. A practical look at user agent test — checking what you send.
Building a User Agent Database
Building a User Agent Database. A practical look at user agent database — collecting and maintaining strings.
The Future of Device Detection
The Future of Device Detection. A practical look at device detection — where identification is heading.