How Do I Auto Pause When User Closes Game

I tried searching for on answer for about half an hour and couldn't find one. When testing my game on my iPhone if I hit the home button and re-open the game, it starts at the main menu. I don't want it to do that. How can I make the game go to the last scene where it left off at when the user re-opens the game. Also, if the user is in the middle of playing on the game scene, I want to make the game automatically go to the pause menu if the user accidentally closes the app or gets a call. So when they re-open the app it goes to the pause menu and they hit resume. Does anyone know how to do this?
Answers
I don't think that it is possible to trigger a pause menu, but as @TShirtBooth said, it will automatically pause it (in multitasking), and resume once the app is opened again.
That would be a nice feature added for the game to automatically go to pause screen.
Could you explain what the hibernate feature even does? I have seen it, but I don't have any idea what it does.
Thanks
Whoa that's awesome! So I could save attributes when the home button is pressed... not as soon as they are changed. Suite!
Thanks!
Have you tested it? SSS said it was exclusively for nook, would be sweet though if it works on ios too.
Thanks and I wondered what that was.