Does the ios Simulator wipe the environment clean every time?
No, it doesn't. You shouldn't have any trouble saving state and reloading it, provided you do it the right way in the first place. For example, people often have trouble because they try to write files inside the application bundle, but the application bundle is always read-only. Save your data somewhere else, such as the app's Documents folder, the defaults system, the Cache directory, etc.
Also, remember that your app's data will be deleted from the simulator if you delete the app, just as it's deleted from the device if you delete the app there. If you simply rebuild the app and run it without first deleting it from the simulator, any data you wrote previously should still be there.