I don't think it makes much sense to count DRM store subscriptions (here 'app downloads') on Android and iOS, since the two platforms have such a different approach to platform design (integrated on iOS vs. connected on Android).

For example, there is nothing similar to a 'Locale plugin' or a 'ADW Launcher Theme' on iOS, and there is no approval process on the most popular Android store.

There is only one DRM Store on iOS, and on some Android devices there is no Store at all.