Sonar Atoll

Sonar Atoll is a logic puzzle of echoes around a tropical atoll at night. The sea around the island is split into rings and sectors. Chests lie hidden on the sea floor. Tap a spot to send a ping: the echo that comes back is the distance to the nearest chest still hidden. One step is one ring in or out, or one sector around the circle. • A ping right on a chest returns 0 and raises it. • Raised chests stop answering, so later echoes point to the ones still hidden. • Spots that can no longer hold a chest fade out (you can turn this off). • Mark Chest lets you note guesses without spending a ping. 50 charts across five areas, from Shallow Reef to Deep Channel, with more rings and chests. Find every chest within par for 3 stars; if all pings run out, the chart restarts. Deep teal water, glowing echo rings and sandy markers. Offline, no ads, no purchases.

First release of Sonar Atoll.