I've had my iPhone 6s for about a year and a half. It's getting slow and having some issues that I think would be resolved if I restored it to original factory settings and set up as a new device. I don't want to use a backup. What downstream effects will this have on my Apple Watch Series 2? I also have Apple Pay set up. Will I also need to restore my watch as well or do I leave it alone? The only thing I have installed is HeartWatch and AutoSleep. i would be OK if I lost all that data.