App update with new name and database

I have an app, which needs to be updated with some changes in it. The name of the app needs to be change and there is a calculater which has the formulas already, but when you closed the app down it don't remember what you have fill in and it needs to remember the last 50-100 lines you have fill in, even when you close the app. I will sent a screen shot and more info when needed.