Switch to appcomat library r21.
Use CardViews for user fragment.
Use CardViews for repository fragment.
Use CardViews for commit fragment.
Use CardViews for issue list.
Use more CardViews.
Fix card background in dark theme.
Use CardViews for issue events and comments.
Remove lines between cards.
Use colored action bar and color highlights.

Colors are derived from the logo and open for discussion.
Replace 'New...' menu items by floating action buttons.