Data entry and syncronization

My app is to be used in the loading of trucks in a stevedoring operation using a weighbridge and automatic loading hopper, discharging mineral sands from a vessel onto a truck and transported to site. The app must have the ability to add each individual trucks journey every time they are loaded and store it in a rolling tally for the Shift Manager and Trucking Supervisor to monitor. This app must have a login username and password to access it with 3 types of users. They are: Trucking Supervisor, Shift Manager and Operator Each separate user has different tasks they can complete once logged in. This app will enable the Trucking Supervisor to set the weights each individual truck is allowed to carry, monitor the variance in weights between each journey, travel time from port to site and back to the port, total trips each truck does per shift and the total tonnage a truck has carried for that day, shift and for the entire vessel. The app will then be able to tell the Trucking Supervisor the average tonnage per hour that the cargo is coming from the vessel, the average tonnage each individual truck is taking and their average round trip time from vessel to site and back to vessel. The Shift Manager is able to look at the app and see a total weight loaded for: each individual truck, each hatch in the vessel eg. Hatch #3 = 5440 tonnes discharged, each shift eg. Day Shift 10/01/16 (12 hour shift) = 4350 tonnes discharged, per hour rate eg. 350t/hr and a rolling total of how much product is left on the ship and each hatch eg. Vessel tonnage remaining = 13250 tonnes, Hatch 3 remaining total = 2120 tonnes. The operator once logged in will select the Hatch in the vessel that the cargo is coming out of eg. Hatch 2. When a truck comes onto the weighbridge, the operator enters the trucks number plate number and then presses ENTER, the app will display the trucks configuration, how much maximum weight the truck can take and where to disperse the cargo. Once the truck is loaded, the operator will enter into the app the weight that has been loaded and then press FINISH TRUCK and this will automatically enter the data into a database that is accessible to all users which shows the rolling total of the cargo discharged off the vessel. If at any time the Operator enters a weight that exceeds the trucks maximum weight a Warning message appears and directs the Operator to contact the Shift Manager and not to let the truck move without further instructions given. Also the Operator has the ability to enter delays such as truck delays and weather delays. All of the data entered gets a timestamp on it fed live from the phone itself. So if the Operator presses a Delay button then the time is automatically populated from the phones clock settings and same when the delay is stopped.