InAppSpy 🔎

Detect in-app browsers (a maintained fork and refactor of detect-inapp)

Installation

pnpm add inapp-spy
yarn add inapp-spy
npm install inapp-spy

Code Examples

Basic

import InAppSpy from "inapp-spy";

const { isInApp, appKey, appName } = InAppSpy();

API Reference

Return properties

{
  isInApp: boolean;

  appKey: "facebook" |
    "gsa" |
    "instagram" |
    "line" |
    "linkedin" |
    "snapchat" |
    "telegram" |
    "threads" |
    "tiktok" |
    "twitter" |
    "wechat" |
    "messenger" |
    undefined; // can be undefined even if `isInApp: true`

  // Pretty printed app name
  // - `appKey: 'tiktok', appName: 'TikTok'`
  // - May change, use `appKey` for programmatic use
  appName: string;

  ua: string; // The user agent figured out by `InAppSpy()`

  skipped: boolean; // debugging, if decided to skip this will be true
}

Parameters (optional)

InAppSpy({
  // To skip a specific appKey from detection
  skip?: {
    appKey: AppKey; // "messenger" | "facebook" etc
    platform?: "apple" | "android"; // use undefined for all platforms or leave blank
  }[];
})

NEW SFSafariViewController detection

With escape link usage: Always include a query string on escape links just in case false positives occur. If query string is present - ignore the detection.

This is a new experimental method to help you mitigate SFSafariViewController issues - ie awkward downloading experience

SFSVCExperimental may give false positives on Safari browser or change with OS updates. Test code on devices before pushing to prod. Feedback is appreciated!

JS usage

import InAppSpy, { SFSVCExperimental } from "inapp-spy";

const { isInApp, appKey, appName } = InAppSpy(); // normal detection

// Async needed - targets Safari 17+
SFSVCExperimental().then((isSFSVC) => /* ...`*/);

React usage

import InAppSpy, { SFSVCExperimental } from "inapp-spy";

export const App = () => {
  const [{ isInApp }] = useState(() => InAppSpy());
  const [isSFSVC, setIsSFSVC] = useState(false);

  useEffect(() => {
    // Async needed - targets Safari 17+
    SFSVCExperimental().then(setIsSFSVC);
  }, []);

  ...
};

Debugging

If SFSVCExperimental returns false positives on your app but not on InAppDebugger, try increasing the maxTime along with debug: true. You are possibly loading additional scripts dynamically immediately after the page loads that is delaying detection.

SFSVCExperimental({
  debug?: boolean; // (default: false) Debug mode - logs to console
  maxTime?: number; // (default: 300 (ms)) This is the max time used to detect if this is Safari and not SFSVC. If you are getting false positives try increasing this number first.
  maxVersion?: string; // (ie: "21.5.1", default: undefined) Max version of Safari to use this detection type - I hope it works forever! This is just in case stop gap if detection stops working :)
});

License

MIT License

Related

• InAppDebugger - Debug in-app browsers. Uses both bowser and inapp-spy libraries.
• Bowser - Browser + OS detection

Thanks

inapp-spy is a fork of detect-inapp with modifications. This wouldn't exist without the original work of the detect-inapp contributors.