Tracking by GPS in China: Google vs Baidu Maps

A friend at Tongji University, Shanghai. Using his GPS coordinates of 31.2820193,121.5083353 he is at the red pin., but this time over 500m west north west of his Google location Baidu Maps.
A friend at Tongji University, Shanghai. Using his GPS coordinates of 31.2820193,121.5083353 he is at the red pin., but this time over 500m west north west of his Google location Baidu Maps.