I'm wondering if I have to declare my personal, used iPhone 6 when entering China as a tourist. Will they make me pay tax on it because it is an expensive phone?
According to travelchinaguide.com that is not necessary:
Question: I’m traveling to China with my Iphone, Ipad, and MacBook. Do I need to declare them and pay the tax when I enter China?
Answer: You do not need to declare and pay the tax for your personal items, such as smart phone, tablet PC, laptop, and digital camera, if within reasonable quantity (one for each). However, if you are taking another brand new phone or laptop with the outer packing and instruction book as a gift for your friend in China, you should declare the new one and pay the tax.
According to my personal experience you don't have to declare it as long as it's not new item. I entered China with my IPhone, Samsung tablet, and Dell Laptop. No problem.