Saving coins

Hello, I am making a android 2d catch game where you have to catch falling objects. Now when you catch one, you'll get one point. What I want now, is that when you are out of lifes, that on the menu is displayed your total of coins. So if you start again, catch some objects and then die again, the coints are added to your total coins. And when you close the app, that it is all stored. I think this is possible with playerprefs but don't know how to do this all.