A free app for Android, by Astro Poly.

Video games, such as those played on mobile phones, are engaging and enjoyable, lowering stress. Gaming causes dopamine release, which makes us feel good. They pose a conundrum and reward you for successfully conquering it, resulting in feelings of competence. It has the ability to induce a state of deep relaxation, which would be comparable to meditation. Just about any game that you find particularly entertaining can be effective in providing a retreat from constant stress, a break from depressive patterns, or a tool to develop positive feelings.

One of the best stress-reliever games for Android is Axe Club. In the game, you must score as many points as possible by throwing axes and traditional darts.