sharedPreferences.intPreference("counter", 0)

  sharedPreferences.stringPreference("string", "")

  sharedPreferences.booleanPreference("seen", false)

  sharedPreferences.longPreference("timestamp", 0L)

  sharedPreferences.enumPreference("notifications", Frequency.ALL)

  sharedPreferences.objectPreference(
    name = "current_user"
    defaultValue = User.ANONYMOUS,
    serializer = someSerializer,
    clazz = User::class
  )

class ExampleActivity : Activity {

  private val sharedPreferences by lazy {
    getSharedPreferences("app-pref", Context.MODE_PRIVATE)
  }

  private val sessionCounter : IntPreference by lazy {
    sharedPreferences.intPreference("counter", 0)
  }

  @Override
  public fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.simple_activity)

    val incrementedCount = sessionCounter.get() + 1
    sessionCounter.set(incrementedCount)

    counter_view.text = "Application was started $incrementedCount times"
  }
}

class ExampleActivity : Activity {

  ...

  private var disposable: Disposable? = null

  override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)

    Observable.just(stringPreference.get())
      .concatWith(stringPreference.onChangeObservable)
      .subscribe {
          text_view.text = it
      }
    }.apply { disposable = this }
  }

  override fun onDestroy() {
    disposable?.dispose()
    super.onDestroy()
  }

  ...
}