= Background
Currently there is no simple, canonical URL on the wiki that directs mobile users to the correct app store. Having a single `Special:MobileAppRedirect` page would allow us to use one link in banners, emails, QR codes, etc., and have users automatically land in the right store.
= Proposed Behavior
- Server-side detection via the `User-Agent` header
- If iOS is detected (`iPhone`, `iPad`, `iPod` in UA string), redirect to the App Store URL
- If Android is detected (`Android` in UA string), redirect to the Google Play Store URL
- If neither is detected, render a fallback page with links to both stores
- URLs configurable via wiki config variables rather than hardcoded?
- A `campaign` URL parameter should be accepted and passed through to the store URLs
- Example: `Special:MobileAppRedirect?campaign=footer_banner_2026`
- For Google Play, appended as `&referrer=utm_campaign%3D{campaign}`
- For App Store, appended as `&ct={campaign}`
- If no `campaign` parameter is provided, redirect without campaign tracking
= Acceptance Criteria
[ ] Visiting `Special:MobileAppRedirect` on an iPhone/iPad redirects to the App Store
[ ] Visiting `Special:MobileAppRedirect` on an Android device redirects to the Google Play Store
[ ] Visiting on a desktop browser shows a page with links to both stores
[ ] `campaign` parameter is passed through to the appropriate store-specific tracking parameter
[ ] Campaign value is properly sanitized/URL-encoded
[ ] Redirect works correctly with and without a `campaign` parameter
[ ] Special page is registered and appears in `Special:SpecialPages`
[ ] Verify we handle iPadOS correctly (Recent iPadOS versions can report a desktop Safari UA.)