How to activate uibutton after a certain number of app launches?

Question

iOS

How to activate uibutton, after a certain number of application launches, after a certain time of activity in the application during the year, until the end of which the button will be inactive? How can code inside the application count visits and time spent in the application in order to display it on the screen?

Answer 1

The first that comes - to save the counter and date of the first start. It is possible though in keychain or more available places.
Then reset to zero in a year and change the date.