title: How do you save your Activity's state when exiting? Android
body: <p>I have a basic app with text inputs, a spinner input, and a second spinner input whose array depends on a setting changed in the Options menu.</p>
  
  <p>Currently, when I press Home or press Return while in my app, I either return to the desktop or cycle back through old inputs i put in recently.</p>
  
  <p>How can I prevent my app from opening multiple instances of itself so that there is only one instance running at any given time, and then how can I save the data entered into inputs, and the settings chosen in my option menu?</p>
  
  <p>I'm a bit new to Java, so I apologize if this is a simple problem.</p>