# GNSS Positioning Using Mobile Devices with the Android Operating System
## 5 Conclusions  
Until a few years ago, low-cost sensors and smart technologies were considered as \"mass-market\" solutions, able to estimate a very approximate positioning and adapt only for navigation or geolocalization. Nowadays, new technologies, new user requirements, new platforms (e.g., Android 8.0), and new challenges have allowed a very powerful \"geomatics\" tool to be brought to our hands. The modern smartphones or mass-market receivers are able to reach very impressive quality, both in static or kinematic positioning, widening the doors to an enormous quantity of applications and research fields. UAV, pedestrian positioning, unmanned ground vehicle, object tracking, security issues, are only a short list of possible domains where the quality reachable with these kinds of sensors could be exhaustive. The improvement is also allowed by the quality of the GNSS signals, the modern infrastructure dedicated to GNSS positioning (e.g., CORS, network, NRTK, etc.), and by the increasing interest due to user communities and big players in the use of these technologies for high-quality positioning.  
In this paper, it is strongly demonstrated that the quality of the signals collected using these technologies is completely able to reach good positioning. Surely, by combining the sensors with a better external antenna, the performances could be better, and other possible applications could be founded. We have presented the results obtained with only one frequency. This is not expected to be the same concerning the performance of all smartphones, especially, because, in 2018, the first smartphone with a dual-frequency multi-constellation GNSS receiver was released (Xiaomi Mi8). This study aimed to show how different results can be obtained in the function of different positioning techniques that can be chosen according to the precision and accuracy requested. Future steps will be to test the performances of other smartphones with other GNSS chipsets installed to provide a deeper overview of possible results obtainable today. Certainly, this will also be done considering the new instruments released on the market in these few last months.  
If a few years ago, smart technologies were only tools for calling and chatting, today, these tools are becoming potential tools for geomatics applications. In the near future, new constellations and signals promise us an improvement in the quality in terms of precision and performance. Therefore, this is only the first step of this new positioning revolution.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Fix** & \multicolumn{3}{c}{**14\%**} \\ \hline  & East & North & Up \\ Precision & \(-0.200\) & 0.532 & 2.336 \\ Accuracy & 0.037 & 0.026 & 0.046 \\ \hline
**Float** & \multicolumn{3}{c}{**86\%**} \\ \hline  & East & North & Up \\ Precision & \(-0.260\) & 0.923 & 2.452 \\ Accuracy & 0.047 & 0.061 & 0.092 \\ \hline \hline \end{tabular}
\end{table}
Table 13: Real-time positioning results using Samsung S8+ receiver and a session length equal to 5 min. Values in meters.  
**Author Contributions:** Conceptualization: P.D. and M.P.; Methodology: M.P. and V.D.P.; Software: P.D.; Validation: V.D.P.; Formal Analysis: P.D. and V.D.P.; Writing--Original Draft Preparation: P.D. and V.D.P.; Writing--Review and Editing: P.D. and M.P.; Supervision: P.D. and M.P. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research received no external funding.  
**Acknowledgments:** The authors would like to thank [PERSON] for helping the authors during the measurement campaign and the reviewers for their helpful comments and suggestions.  
**Conflicts of Interest:** The authors declare no conflict of interest.