Test results in China (Fijian province), China Mobile 100Mbps Fibre, wireless
1) purevpn openvpn configuration works.
Update: the app is also work now with HK server.
2) My simple V2Ray SG server on Google VPS works pretty well.
3) Windscribe free version does not work. It is reported the paid version can work in China.
4) Astrill explicitly mentioned that the free Android version does not support China. They are confident that Astrill VPN will work in China but you need to pay, no free 7days trial in China, unlike other places.
5) 几鸡机场SSR provider free tier works.
https://ji-bn.pw/
6) Free VPN xiaoming VPN and Wang VPN are working and pretty fast (only for testing purposes, not recommend to use on phone, probably can be used for TV boxes with not important account)
7) Some free-ss.site SS servers are also working.