Save Calculator Result

Hello, 

I would really appreciate help on how to allow for the calculator result to be available on another page. Or at least, if the user clicks on another screen, when they click back to the Calculator Widget, the result is still there. For my app, we would like the Calculator result to also appear when we go to the "Recommendations" screen. ( the number will show on the next screen(If this is difficult to do, how do you make the result save until the user clicks a "clear" button" of some sort. 

      Something that we are not sure if possible is to make the result of Calculator one and have a second calculator with different variables. The second calculator's final result is ( calculator 1's result) times calc 2's own variables. 

This is my app.

https://ibuildapp.com/projects.php?action=info&projectid=1161850

 I will really appreciate any help because I'm just starting out with making apps and still have a lot to learn. 

Thank you so much!

Shan Y