The game does not perform when there is a weak cell signal or there's no cell signal at all, nor does it perform when in your iPhone is in "Airplane" mode, I have the 256 gb 7plus. https://www.Google.co.uk/url?q=http://seiklused.com/%ED%96%89%EC%9A%B4%EC%9D%98-%EB%AC%B8-%EC%9A%B0%EB%A6%AC%EC%B9%B4%EC%A7%80%EB%85%B8/