Android :: Best Way To Add Configuration UI To Application?

I have a simple Android application that loads a page in a WebView, then most of the real work is done by the server-side scripts. Everything is working great, except that I currently have the page URL hard-coded in the Android application, sort of like this:
mWebView.loadUrl("https://www.my-application-url.com");

This was fine until this morning when I was asked to to make it so that the user is prompted to enter the URL the first time the application run, and the URL that is entered by the user is then saved and used automatically by the application from that point onward. I was also asked to make it so that the user can change the URL if they choose to do so. The reason I was asked to do this is so that users can install the server side of the application on their own servers and my Android application will be able to connect without me having to write a custom version for each user, with their URL hard-coded into the application.

I am unsure what is the best way to handle this in Android. It seems that I probably need to add some type of configuration interface to the application that is shown by default on the first run, then only when the Menu button is pressed on the following runs. From this configuration interface I guess I would then get the URL from the user and serialize it for future use. What is the best way to accomplish this?