I use Google maps with a VPN on my (Nexus) phone and it works well. It might bounce around a little now and then, but I only use walking or public transit directions and have had no trouble. Strangely using Strava in Hefei last weekend it was almost impossible to get a GPS lock on my phone even open areas, but Google Maps got it in seconds.

An alternative that you might try is something like Gaia or OSMAnd+ which have maps that you pre-download and thus use 0 data. These use publicly sourced maps. I don't use them that much here, but they also have walking trails that the others don't cover. I use them for trail running in other parts of the world (and this coming weekend in Hangzhou).

Dr. PITUK

P.S This just reminded me to update my map for the weekend on OSMAnd+. It is possible to choose the language of street names and English (and Chinese) seem to work fine at least in Jiangsu and Zhejiang provinces.