Checking User number
Sorry if this question has been asked already.
Here's the question:
I want to figure out which user has used my application and how many times.
Each user has been given a participant number.
When they first land on the application, I would like them to enter their participant number.
Once they close the app and use the application again, I want the application to remember their participant number and log in the database that the user is accessing the application again.
Is this possible and if so, how would I go about doing this?