Shark for Root is another best illegal android app that allows you to track activities of other mobile users. It works great when used on rooted devices. You can use it on 3G, WI-Fi and FroYo tethered networks.
If you have someone to whom you want to track, then you must install this application on your device. You can use those android apps to hack someone's Wi-fi and enjoy the free internet. So, without wasting any more time, here's a list of some best illegal android apps which you can use for hacking purposes.