I have a 6s as does my wife and son, and an iPhone 5 before that, and we've never had these issues. (Battery did die though, eventually). The phone that *does* often just randomly shut off on me is my Galaxy S4, which is my work phone. I've changed the battery on that twice already. Also, my Galaxy Tab A freezes, but to a much lesser extent than the S4. Overall I have more reliability issues with Samsung/Android than I do Apple. It's the pick of the draw, all these things have the potential for failure.