Reviewed in Icon Packs - worth the buy -
Flatro- A round flat look icon pack bringing Retro and Minimal together in this wonderful display of work. Ryan Kelly never disappoints with his Icon packs. Definitely worth the buy- Ryan Kelly makes the list- See all his work at https://play.google.com/store/apps/developer?id=RyanMKelly
alphajohnx - is the icon pack I have been using the most recently, made me fall in love with circular icons.