Runtime Detection

Use these exports to decide when bridge calls should run, and how to deliver the SDK in browser contexts.

Detection exports

Export	Type	Notes
isNative	boolean	Computed once at module load
platformInfo	object	Snapshot at module load
hasMessageHandlers()	function	Checks window.webkit.messageHandlers.pwakit
hasPWAKitInUserAgent()	function	Checks PWAKit in user agent
detectPlatform()	function	Returns ios, browser, or unknown
getPlatformInfo()	function	Re-evaluates full detection result

Recommendation

For dynamic checks, prefer getPlatformInfo() rather than relying only on isNative.

Runtime behavior

Environment	Detection	Bridge calls
PWAKit iOS shell	getPlatformInfo().isNative === true	Available
Regular browser	usually isNative === false	Reject with BridgeUnavailableError
SSR/Node	window absent	Not available

Browser bundle (no bundler)

Use the IIFE bundle when you want script-tag usage:

<script src="https://cdn.jsdelivr.net/npm/@pwa-kit/sdk@latest/dist/index.global.js"></script>
<script>
  const { isNative, push } = PWAKit;
  if (isNative) {
    push.subscribe();
  }
</script>

The global variable is window.PWAKit.

Bridge events

PWABridge dispatches native events as browser CustomEvents with pwa: prefix.

Subscribe

import { bridge } from "@pwa-kit/sdk";

const unsubscribe = bridge.on("push", (data) => {
  console.log("Push payload", data);
});

// Later
unsubscribe();

One-time listener

bridge.once("push", (data) => {
  console.log("First push only", data);
});

Bridge call options

bridge.call(module, action, payload, options) supports:

• options.timeout (ms)

Default timeout is 30000 ms.

Fallback pattern

import { BridgeUnavailableError, getPlatformInfo, ios } from "@pwa-kit/sdk";

export async function authenticateIfNative(): Promise<boolean> {
  if (!getPlatformInfo().isNative) return false;

  try {
    const result = await ios.biometrics.authenticate("Continue");
    return result.success;
  } catch (error) {
    if (error instanceof BridgeUnavailableError) return false;
    throw error;
  }
}