I realized dat almost all d iPhones I buy to sell have no push certificates. Push certificate is what apple iPhones use to push ur notifications to u when u get them on Facebook,twitter,ebuddy,etc. If u v these apps installed n u don't av push certs, d iPhone will continuously b looking for it, thereby draining ur phone battery massively. Also if a friend is chatting wit u, u av to start d chatting app to see d msg. This is not d way ur iPhone shd work. If u want to b sure u av valid push certificate, install IPUSHER from d AppStore free, open d app and test ur push, if u get d msg dat ur 'push is working fine', u av no problem, if it gets stuck at 'pls wait', then ur push ain't working. If u want to enjoy ur iPhone (3G,3GS,4), make sure ur push notification works. for more details contact 08053250698 or email tumababa247@yahoo.com