Basically don't use HTML
If you want a great UX don't use any webviews unless you want to display something from the web or very plain HTML (like for Legal Stuff). WebViews are less responsive then Native Android and you will to deal with more Fragmentation issues as well.
search for Custom View in developer.android.com
If you just want an image with different areas of interaction, you can extend an ImageView or a View and control the interactions by setting the onTouchEvent with a function of your choosing.
(can't post links as I'm new here)