how is the Internet wifi services in Guangzhou?

Generally speaking, people can easily access to the Internet by connecting Wi-fi in this city, such as fast food restaurants (MacDonald), cafes (Starbucks), hotels, railway/subway/airport and large shopping malls. But if you wanna use the Map App in this city, you'd better to buy a sim card. The wifi service doesn't cover the whole city.
Or maybe you can try to download the offline map on your mobile phone.