Blind Drop: Sonar Descent

Blind Drop is a one-handed arcade game about steering a probe down a dark trench for as long as the battery lasts. You can't see the walls. Tapping the screen sends out a sonar wave from the probe, and anything the wave reaches lights up for a couple of seconds before fading again. That's your only way of seeing what's ahead. A short tap gives you a small, cheap ping that travels with you. Holding your finger down for a moment gives you one that covers the whole screen but costs more battery. Dragging left or right steers. The trench is generated as you fall, so it's different every time. It narrows and drifts, rock juts out from the walls, and every so often a column splits the corridor in two and you have to pick a side. It's also inhabited. Eels lunge from burrows, jellyfish drift across the open water, and deeper down anglerfish wait in the walls with a glowing lure. Sonar only shows where a creature was when the wave reached it, so you're always guessing a little. Bumping into anything takes a chunk out of the battery. The battery also drains slowly on its own, a little faster the deeper you go. Battery caches are scattered along the walls. None turn up in the first 250 metres, since you start fully charged. After that they're most common in the upper stretch and get rarer the deeper you go, and like everything else you only see them when a ping finds them. Every ping makes a sound, and the walls and creatures it reaches click back from the side they're on. If you'd rather play in silence, sound can be switched off from the main menu. Apart from a small pause button, there's no interface drawn on top of the game. The probe's own glow tells you how much battery is left (it flickers and sparks when you're nearly out), depth markers are carved into the trench walls every hundred metres, and a band across the shaft marks each of the four depth zones. A line of small, faint diagnostic text along the bottom of the screen is the only text you'll see during a run. Runs are short, usually a minute or two. There's a Game Center leaderboard for the deepest point reached if you want to compare with other people, and three colour schemes (green phosphor, amber, and a blue wireframe) to pick from on the main menu. The game has no ads, no in-app purchases and no account. It doesn't collect any data, and it works offline.