Supercell has created some of the most popular mobile games of the last couple of years. Clash Royale is a strategy game that combines collectible card games with tower defense mechanics and borrows its setting from the incredibly popular management sim, Clash of Clans.
Clash Royale was released globally on March 2, 2016 and became the most downloaded and top-grossing app on the US iOS App Store. Since most card battles in Clash Royale last just a few minutes it is perfect to play at work. You can play just a single match, or keep playing and collecting cards until you decide to do some actual work.