I recently published RedCorners.ExifLibrary, a NuGet that lets you read and write EXIF metadata in image files. This is basically a fork of the ExifLibrary project by oozcitak, with four minor changes:

• It removes dependencies to System.Drawing, making the library work across all .net Standard 2.0 compatible runtimes, including Xamarin.iOS and Xamarin.Android.
• It adds a conversion helper method for going back and forth between floating point or Degrees/Minutes/Seconds representations for coordinates.
• It adds helper methods to quickly read and write GPS coordinates in the image files.
• Everything is moved to the RedCorners.ExifLibrary namespace, in order to make it possible to use both the original library and my version of it simultaneously.
• It has been tested on Xamarin.iOS, Xamarin.Android, .NET Core and .NET Framework on JPEG images.

You can get the NuGet from here: https://www.nuget.org/packages/RedCorners.ExifLibrary

Some quick examples:

using RedCorners.ExifLibrary;

// Read GPS Coordinates
var file = ImageFile.FromFile(Path);
var coords = file.GetGPSCoords();
if (coords.HasValue)
(Latitude, Longitude) = coords.Value;

// Write GPS Coordinates
var file = ImageFile.FromFile(Path);
file.SetGPSCoords(Latitude, Longitude);
file.Save(Path);