We're proud of being the designer of data transfer program on mobile phones with more than 20 years of experience and hard work in projects dams:(Khoda afaring ,Siyah bishe ,Gotvand ,Dariyan) ,the subway system and etc. Facing problems of surveying, Ive been trying to design applictions, android, VB, lisp and all programs which are in our telegram channel @naghshebardaraneparseh. Your mobile most have OTG ability. Connect the cable to mobile and total station. Select com parameters equal to total station Baudrate, Databits, Parity, Stop bit . You can read help menu and use app. When you transfer data to your mobile then you can use other apps to control the tunnel ,cut and fill ,draw plan , Topography , section , 3d picture in autocad , Travese , .. You can see other apps also you can join to my channel and send serial for receiving password. I say that we dont need expensive total station because apps can help us.