Vivo 1606 model is used for the study of standalone use of smartphone as a positioning device with FM supported location (Assisted- GNSS) for GPS, GLONASS, BeiDou. The observations were collected at every 5-minute interval for the analysis. The sessions were divided into three shifts morning, afternoon, and evening to check the accuracy in real time static mode. Mobile topographer app was used for capturing WGS-84 geographic coordinates having horizontal and vertical position with time in an urban environment to analyze which time of a day is good and till what time one can take GPS reading to get the minimum errors using smartphone. It is found that the positional dilution of precision (PDOP) stabilizes in about 35 minutes and minimizes at a value 0.2. The observations beyond have minor changes, so the position at 35 minutes has been used as reference for evaluation of statistical parameters. The real time observations of horizontal, vertical, and positional accuracy seem to increase with time as the PDOP, HDOP, VDOP values decrease i.e. improves with time. It has been observed that, RMSE of PDOP is 0.0485 and HDOP is 0.029 during afternoon is higher as compared to morning and evening values. The study suggest that the preference of survey shall be in the order: morning, evening and afternoon, which may further depend on the season at time. The survey during noon in summers can give much higher values of PDOP and thus the survey can be carried out during morning and evening times preferably.