title: How to get keyCodes from Android mobile device keyboard?
body: <p>Currently, I am facing a problem on a mobile device. I have an input field where only some keys are allowed to be pressed: e.g. only the numbers 0–9. It works fantastic on a web browser. But when I open it in my Android mobile device it fails.</p>
  
  <p>I have used <code>keyup</code> and <code>keypress</code>. <code>keyup</code> is working but I want to know which key fired the event from the mobile keyboard. How would I get that?</p>