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Trope, an app by Opal Limited, is available for US$3.99 at the App Store.
Two weeks ago, when I reviewed an application called "Air," I referred to it as the follow-up to a similar app called "Bloom." One of the developers, Peter Chilvers, wrote in with a point of clarification: Air was not actually intended as the official follow-up to Bloom, an app that Chilvers wrote in collaboration with Brian Eno. The real follow-up, also created by Chilvers and Eno, is called "Trope."
All three -- Bloom, Air and Trope -- are generative music applications. In other words, they're used to create free-flowing, ambient music, and you don't have to be particularly skilled at an instrument in order to use them. When it comes to making music on a small touchscreen, that's a good thing -- even if you're a virtuoso pianist, it won't count for much when you're dealing with a three-and-a-half-inch keyboard that gives you no tactile feedback.
I thought Air was sort of limiting -- rather than giving you a set of aural finger paints, it gives you a color-by-the-numbers sketch. It boxes you in by separating the screen into a dozen zones. Trope, like Bloom, lets you go freestyle.
Different Style
In Bloom, you create music by tapping a colorful touchscreen, producing a series of tones that sound like plucks on harp strings and repeat at a set interval. All the while, a low drone hangs in the background, and everything sounds in-key. The overall effect is that of a xylophone being played in an echo chamber, with added eye candy --serene, relaxing and oddly fascinating.
Trope plays along very similar lines. You first get an option to listen or create (listening basically just puts the app on autopilot). Select Create and you're taken to a color-shifting background that plays music in response to your touches.
However, control is different in Trope. Instead of short notes in response to taps, Trope is best used with broad swipes that fade tones in and out and produce colorful squiggles that blur and recur on the screen. The background sound isn't so much a steady drone as it is a accompanying note- and squiggle-maker. The sounds you create will repeat at seemingly random intervals rather than at a set pace. Basically, you get an extra helping of eye candy and less control over the sound. Again, the result is serene, relaxing and oddly fascinating, in a mellower sort of way.
Mood Indigo
Like Bloom, Trope gives you a handful of options you can use to shape the experience. A volume slider is provided, you can clear its memory of recent gestures with a button or set it to clear with a shake of the iPhone, and you can set a sleep timer in case you drift off (like I said, this is mellow stuff -- it's a nap app, not mood music for a high-impact cardio workout).
Speaking of mood, there's also a Mood section in Trope's options menu that gives you some ways to control what you see and hear. Along the top are several shapes to choose from -- these are basically different brushes you can use to paint the sonic canvas, producing a different appearance.
You can also choose from among a list of moods with various strange names like "Sodalis," "Eudoraea," and "Orenia." As best as I can tell, you get a different color palate and slightly different sound accompaniment depending on which mood you pick. You can also set the mood to shuffle.
Bottom Line
Apps like Trope and Bloom are like doodling with music. It's virtual Zen-garden raking with a soundtrack.
Trope hits the right note as a follow-up to Bloom -- it uses a similar setup and design, but it's got just enough tweaks to differentiate itself from its predecessor. If you've been using Bloom for months and wish you could do a few more tricks with it, consider Trope to be a $4 update. If you've never used an Eno/Chilvers app but think what's been described above sounds remotely interesting, either Bloom or Trope would be a good place to start.
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