Whats the best way to have a connected sub window for a monogame app.

For example lets say i wanted to create a paint program in monogame or some other such app with a Color window that opened seperately from my monogame window.

http://i936.photobucket.com/albums/ad207/xlightwavex/miscellaneous/WindowExample_zpsntxrdjnm.png

What would i look into to do that should i open another monogame window.
(if so how to do that from the main app) or use something else.

Any references, opinions, thoughts, tutorials or examples are welcome.

I think opening Forms or Wpf windows should work if you add the references.
You need to set the owner property to make it a child (wpf. I dont remember about forms)

Then to communicate with it should be the same thing as with a regular c# app. (properties, binding…)
Maybe the hardest part will be how you measure time in the window in order to use gametime and have both synced.
Or a 2nd mg window but harder to do the sy’c and pass data will need some lines of code