guess platform, might need tweaking still

src/Platform.js

@@ -26,10 +26,32 @@ export const Platform = createEnum(
 	"Linux"
 );
 
-export function guessApplicablePlatforms(userAgent) {
-	// use https://github.com/faisalman/ua-parser-js to guess, and pass as RootVM options
-	return [Platform.DesktopWeb, Platform.Linux];
-	// return [Platform.MobileWeb, Platform.Android];
+export function guessApplicablePlatforms(userAgent, platform) {
+	// return [Platform.DesktopWeb, Platform.Linux];
+    let nativePlatform;
+    let webPlatform;
+    if (/android/i.test(userAgent)) {
+        nativePlatform = Platform.Android;
+        webPlatform = Platform.MobileWeb;
+    } else if ( // https://stackoverflow.com/questions/9038625/detect-if-device-is-ios/9039885
+        (
+            /iPad|iPhone|iPod/.test(navigator.platform) ||
+            (navigator.platform === 'MacIntel' && navigator.maxTouchPoints > 1)
+        ) && !window.MSStream
+    ) {
+        nativePlatform = Platform.iOS;
+        webPlatform = Platform.MobileWeb;
+    } else if (platform.toLowerCase().indexOf("linux") !== -1) {
+        nativePlatform = Platform.Linux;
+        webPlatform = Platform.DesktopWeb;
+    } else if (platform.toLowerCase().indexOf("mac") !== -1) {
+        nativePlatform = Platform.macOS;
+        webPlatform = Platform.DesktopWeb;
+    } else {
+        nativePlatform = Platform.Windows;
+        webPlatform = Platform.DesktopWeb;
+    }
+    return [nativePlatform, webPlatform];
 }
 
 export function isWebPlatform(p) {

src/main.js

@@ -24,7 +24,7 @@ export async function main(container) {
 	const vm = new RootViewModel({
 		request: xhrRequest,
 		openLink: url => location.href = url,
-		platforms: guessApplicablePlatforms(navigator.userAgent),
+		platforms: guessApplicablePlatforms(navigator.userAgent, navigator.platform),
 		preferences: new Preferences(window.localStorage),
 		origin: location.origin,
 	});