I love napping. I could make excuses about it making me more productive and alert, but the simple fact is that naps and sleeping are a great personal pleasure. It's not easy to nap just everywhere and at anytime. I find that "white noise" and soothing sounds can really help me to nap on airplanes, while waiting in various lounges, or just when I want to catch a quick power nap. I've recently tested Sound Circle, an ambient noise app. Sound Circle requires iOS 7.0 or later and is compatible with iPhone, iPad, and iPod touch. This app is optimized for iPhone 5. The app is free with a $1.99 in-app purchase for the timer and playlist functionality.
When using an app to provide soothing sounds for napping I have just a few simple requirements. First, the app should present me with a selection of "environments" to select from, like softly falling rain, gentle waves, twilight in the forest with birds and insects, or generated electronic noises. The second basic requirement is a timer to let me confidently fall asleep knowing that I'll be awakened on time. Sound Circle does offer a nice, basic selection of sounds, but you have to purchase the timer feature.
I do like how Sound Circle allows me to select multiple sound samples and combine them, setting each sound at the desired and separate volume. But I found the controls balky and unresponsive. The app also provides several built in piece of music. I'm not sure exactly how many, because each time I tried to move past the seventh selection the app crashed.
Sound Circle is best used with headphones to give a full immersive experience. Professional nappers like myself also use a sleep mask to enhance the experience.
The lack of a timer is a real shame. Frankly, it makes the app a non-starter for me. While I'd be open to purchasing sounds or other features, a timer is basic required functionality. Without it I just can't use this app for napping or sleeping when I'm concerned with waking at a specific time.
Sound Circle offers a playlist option, but that's also part of the in-app purchase. Frankly, if you want to sleep to a playlist of your own music you can build your own with the built-in Music app and simply set a timer using the Clock function. I don't nap as easily to music (OK, soothing classical or ambient music can work), but many people enjoy falling asleep this way. You just don't need another app for that.
My recommendation for music to sleep by? Brian Eno's Music For Airports. Especially nice for use when sleeping in airports and awaiting delayed flights.