Considerably different. Mock location data simply provides the location you want over ADB. It is a supplied value.

It doesn't need ADB. There's an app for that: https://play.google.com/store/apps/details?id=com.lexa.fakeg...

So it is similar in that you could conceivably have an app that manages fake contact lists' data.

True, but that is just performing the same data mocking that the ADB method uses. It really doesn't change my statement.