Hybrid App Development: Using WebView for Native‑Web Interaction on iOS and Android

The article introduces hybrid app development, where a native container (WebView) loads web content to achieve cross‑platform code reuse, and explains why hybrid solutions are attractive for rapid updates despite not fully solving native performance gaps.

iOS UIWebView – The tutorial shows three loading methods ( - (void)loadData:… , - (void)loadHTMLString:baseURL: , - (void)loadRequest: ) and demonstrates a simple view controller that creates a UIWebView, loads a local HTML file, and displays it in the simulator. It also lists interaction APIs such as - (NSString *)stringByEvaluatingJavaScriptFromString: and navigation callbacks, plus navigation methods ( canGoBack , goBack , etc.).

Android WebView – The Android counterpart uses android.webkit.WebView . After declaring the INTERNET permission, the article presents loading APIs ( loadUrl , loadData , loadDataWithBaseURL ) and shows how to add a <WebView> element in a layout XML file. It then enables JavaScript via WebSettings.setJavaScriptEnabled(true) and loads a local HTML asset.

Native → JavaScript – For iOS, the code uses stringByEvaluatingJavaScriptFromString to invoke a JS function defined in the loaded HTML. For Android, it distinguishes pre‑KitKat ( loadUrl("javascript:…") ) and KitKat+ ( evaluateJavascript ) approaches, providing a helper method that selects the appropriate call based on the OS version.

JavaScript → Native – On iOS, the shouldStartLoadWithRequest: delegate intercepts a custom URL scheme ( hybrid:// ) to extract parameters, parse JSON, and dispatch actions such as forward navigation or opening native UI. On Android, a JavaScriptInterface class annotated with @JavascriptInterface exposes a showToast method, which is bound to the WebView via addJavascriptInterface and invoked from JavaScript.

The final section reflects on the trade‑offs of hybrid apps: they excel at hot‑updating frequently changing modules but still lag behind pure native experiences, suggesting that true cross‑platform solutions may involve shared native codebases combined with selective hybrid updates.