I have a web-app (HTML+JavaScript) with a simple HTMLInputElement (type="file") for bringing up the File Browse dialog for picking a local file. No weird hiding or CSS tricks.
<input type="file" id="filePicker" class="fileInput" accept=".txt"/>
It works fine in both browser mode or in stand-alone mode (i.e. installed onto the home screen) under iOS as well as in Android.
However, in iOS stand-alone mode, if the "Home" button (iPad/iPhone's physical button) is pressed BEFORE the File Browse operation is "Done" or "Cancel"-led, the not-yet-dismissed File Browser dialog will be gone on returning from the Home Screen. Unfortunately, the same Input element will no longer be able bring up the File Browse dialog - ever, even after reloading the app. Everything else (buttons, UI elements, mouse clicks, etc) works normally. To get the file picker button working again, the entire app (i.e. the Safari instance) has to be killed (by flicking up the tasks view) before the File Browse dialog can be brought up again.
This does not happen in browser mode - the browser will keep the unfinished File Browse dialog up after returning from the Home Screen.
Does anyone know a way to get around this serious problem? Is that a known iOS bug?