Documentation Index
Fetch the complete documentation index at: https://mintlify.com/michael-tiger-2010/wyvernjs/llms.txt
Use this file to discover all available pages before exploring further.
After tf.init(), the device object on your context exposes a comprehensive snapshot of the user’s environment, including touch capabilities, color scheme preference, browser type, OS, screen and viewport dimensions, network connectivity, battery status, and geolocation support. Most properties are populated synchronously at init time; a handful update reactively as system conditions change.
Touch
| Property | Type | Description |
|---|
device.isTouch | boolean | true if 'ontouchstart' in window or navigator.maxTouchPoints > 0 |
device.touchPoints | number | navigator.maxTouchPoints — 0 if unavailable |
Color Scheme
| Property | Type | Description |
|---|
device.isDarkMode | boolean | true if prefers-color-scheme: dark |
device.isLightMode | boolean | true if prefers-color-scheme: light |
device.isDarkMode and device.isLightMode automatically update when the OS color scheme changes — no need to re-call tf.init().
Network
| Property | Type | Description |
|---|
device.isOffline | boolean | true if !navigator.onLine — updates on online/offline events |
device.connection | object | null | { effectiveType, saveData, downlink, rtt } from the Network Information API, or null if unsupported |
device.isOffline updates automatically when the browser detects a connectivity change.
| Property | Type | Description |
|---|
device.isMobile | boolean | true if the UA contains Mobi, Android, iPhone, iPad, or iPod |
device.isDesktop | boolean | true if the UA does not match the mobile pattern |
Browser
device.browser is an object with one boolean per major browser. Note that isSafari excludes Chrome (which also includes “Safari” in its UA string).
| Property | Detection |
|---|
device.browser.isChrome | /Chrome/i in UA |
device.browser.isFirefox | /Firefox/i in UA |
device.browser.isSafari | /Safari/i in UA and not Chrome |
device.browser.isEdge | /Edg/i in UA |
device.browser.isIE | /Trident/i in UA |
device.os provides UA-based operating system detection.
| Property | Detection |
|---|
device.os.isWindows | /Windows/i in UA |
device.os.isMac | /Macintosh|Mac OS X/i in UA |
device.os.isLinux | /Linux/i in UA |
device.os.isiOS | /iPhone|iPad|iPod/i in UA |
device.os.isAndroid | /Android/i in UA |
Screen
device.screen reflects window.screen values captured at init time.
| Property | Description |
|---|
device.screen.width | window.screen.width |
device.screen.height | window.screen.height |
device.screen.orientation | window.screen.orientation.type, defaults to 'portrait-primary' if unsupported |
device.screen.pixelRatio | window.devicePixelRatio, defaults to 1 if unavailable |
Viewport
| Property | Description |
|---|
device.viewport.width | window.innerWidth at init time |
device.viewport.height | window.innerHeight at init time |
Battery
device.battery starts as null and is populated asynchronously via the Battery Status API after init. Once resolved it contains:
| Key | Description |
|---|
level | Charge level as a float between 0 and 1 |
charging | true if currently charging |
chargingTime | Seconds until full charge (or Infinity) |
dischargingTime | Seconds of remaining battery life (or Infinity) |
Geolocation
| Property | Type | Description |
|---|
device.hasGeolocation | boolean | true if 'geolocation' in navigator |
Quick reference example
tf.init();
if (device.isDarkMode) applyDarkTheme();
if (device.isTouch) enableTouchUI();
if (device.isOffline) showOfflineBanner();
if (device.hasGeolocation) promptForLocation();
console.log(device.browser);
// { isChrome: true, isFirefox: false, isSafari: false, isEdge: false, isIE: false }
console.log(device.os);
// { isWindows: false, isMac: true, isLinux: false, isiOS: false, isAndroid: false }
console.log(device.screen);
// { width: 1920, height: 1080, orientation: 'landscape-primary', pixelRatio: 2 }
console.log(device.viewport);
// { width: 1440, height: 900 }
console.log(device.connection);
// { effectiveType: '4g', saveData: false, downlink: 10, rtt: 50 }
// or null if the Network Information API is not supported
// Battery is async — check after a tick or in a listener
setTimeout(() => console.log(device.battery), 500);
// { level: 0.87, charging: true, chargingTime: 1800, dischargingTime: Infinity }
