I have been struggling with field unit conversions for many years now. The service data is NEVER in the units you desire or need in your map. I would like to see the ability to support an automatic unit conversion based on my user preference.
Think of how a date time field is presented by the web clients. You can store a date time field using any time zone you like and the client software will always convert this to the user's local time automatically.
Why can't we do the same thing with other numeric fields?? It would be fairly straightforward. The user's profile would allow you to set a desired unit type for Speed, Distance, Elevation, and even Volume. Service Layer field details now support the ability to include a description and to declare the value type. All we need is to add the units of the field. With the user's preference and the field's unit specification, the client software can easily convert from one unit to another automatically without adding additional code to the user's web map.
With this feature, global maps would be able to localize their data for users all across the world without the need for a custom map per location.
