I've heard that, as far as conserving battery, connected to Wi-Fi is better than 3G, but if you leave Wi-Fi on and all it does is search for an open network, that drains even more battery than 3G. Is that all right? Second, is there a way to turn off all Internet activity, such as while sleeping? I would use Airplane Mode, but I still want to be able to get calls and texts in the case of emergencies. Thanks.