Not every app is free in the app store. This doesn't mean that they are paid for ever. There are days when the developers decide to make them free for a limited time, or some third party encourages the developers to do so so that the app gains fame really fast. There are also 'bundles' once a while (Android/Mac/PC apps), but I haven't seen that in the iOS world yet.
I discovered Appgratis™ recently and that really changed a whole lot of this equation. The agenda is simple
