Write an iPhone application -- 2

Hi - I need someone with very good experience with Core Motion and Swift 3 in IOS to improve the calculations on an existing app. It is an Iphone app to use the Iphone as a measuring device (like a ruler) to measure tables, etc. These are changes I need: 1) Improve the calculation of distance travelled (current codes don't work well). Take into account the speed in which the phone is moving. The result has to be consistent! 2) Allow measurements in all directions including circular objects 3) Add meters as unit of measure to display on screen 4) On the UI, add a marker pointer to show the user where to measure from Use Swift 3 and Core Motion as technologies I've attached existing codes.