Maybe, $0.99 is popular... But 0$ and open-source are more popular, I hope. Though it's difficult to compare... Quality isn't quantity. Compare: two or three (don't remember) different theremins in iPhone app store, all with 0.99$ price, and one free open-source theremin on maemo.org. And centralized app store gives artificial restrictions. Would it be possible to have unlocked FM transceiver if the only way to install an application was through centralized censored App Store? ~~~~~~~~~~~~~ Somewhat subjective.