A few months ago, I went to Shanghai. Before going to China, I setup the Shadownsock on my server. My 4G network is roaming SIM card. I can surf on Google Map over my SIM card without any proxy or VPN. To prevent from sniffing, I always connect to the network via OpenVPN with non default port.

In hotel, the Wi-Fi network cannot connect to many sites. Sometimes, I can connect the Internet via OpenVPN, but, Shadowsocks is more stable.