I wrote some test code:
pos_source = QGeoPositionInfoSource::createDefaultSource(this);
then get the last postion every 30 seconds by :
and save the positions.
I found that these positions are not accurate and they are seem to be generated by cellid,not by satallites.
if pos_source->lastKnownPosition(true) is used,then the positions are always not valid.
my test device is 5230,it support A-GPS.
at the same location and on the same phone,the OVI map can get accurate position in 10 seconds.
what should I do to improve it?