Android WebView App With File Transfer

Java, JavaScript, Mobile App Development, Android, Kotlin, Mobile Development, Android App Development, Android Studio · Android WebView App for EstiBill – Source Code Required I have a fully responsive web application called EstiBill, an online estimate, quotation and invoice/billing application. The website is already complete and working. I need an Android WebView application that provides a smooth, native-app-like experience. Main Requirements: • Open my EstiBill web app URL inside Android WebView and keep normal navigation inside the app. • Full support for PDF downloads. PDFs generated by my website must download correctly to the user's device with the correct PDF filename, not a random/encoded filename. • Full support for file uploads, including camera, gallery and Android document/file picker. • Support WhatsApp links, phone links and other external links correctly. • JavaScript, cookies, sessions/login and local storage must work properly. • Show a smooth loading/progress indicator while pages are loading. • Proper offline/no-internet screen with Retry button. • Android Back button should navigate to the previous WebView page when possible. • When the user presses Back from the EstiBill Home/Dashboard, show a professional confirmation dialog: “Do you want to exit EstiBill?” – Yes / No, inste