The Good Thunderspace gives you a realistic thunderstorm experience, with 3D stereoscopic sound and simulated lightning.
The Bad You only get a couple of storm types with your purchase. There is no sleep timer.
The Bottom Line Though it's a niche product, Thunderspace is a worthwhile download, with realistic-sounding storms that make for a relaxing experience.
A realistic storm simulator for relaxation
Thunderspace is an audio thunderstorm simulator with 3D stereoscopic sound that's perfect for relaxing with headphones, and it has one especially cool feature.
Unlike other audio storm generators, Thunderspace adds synchronized simulated lightning. Even further, the 3D stereoscopic sound makes the storm seem as if it's all around you. You're not going to get this experience simply by playing the audio through your iPhone, so you should plug in some earphones. I tried with both earbuds and headphones, and the latter definitely brought out more of the bass, which is especially cool when there's a lot of thunder.
Thunderbolts and lightning
The feature that sets Thunderspace apart from other apps is the capability to simulate lightning. It uses the flash on your iPhone to send one or more light pulses and soon after you'll hear the thunder that matches the lightning strikes. The idea is that you'll start a "storm," then place your iPhone face-down on something so it's out of your direct view. This way the lightning seems more realistic than actually seeing the flash on your iPhone go off. It's not perfect, and I noticed some lightning flashes that weren't followed by thunder, but most of the time it's quite realistic. Don't worry about the screen staying on either; Thunderspace uses your front-facing camera to detect when your iPhone is face-down and turns off the screen immediately.