Ok, I downloaded WeChat here in the U.S. figuring I might want to use it to communicate while in China later this month. A few of my friends there use it so I figured I would see what the fuss is about. However, it's requiring my phone number to sign up. Will this work for me in China if I provide a U.S. phone number? Why does it even need my phone number? I was only planning on using the app while on wifi.

Any advice is appreciated. I've never used an app like Whatsapp or Viber while traveling internationally so I'm not sure if I really understand all these apps. But I don't plan on using my iphone other than on wifi to avoid international data rates.