Firewall iP, the first and only Firewall for the iPhone, has been updated to 1.45 and now supports iOS 4.0. YEAH! You are able to protect your device and your privacy right from the beginning of 4.0 
!
Available via Cydia and RockApp for just $2.99!
If you don't know about Firewall iP:
Firewall iP is the only security app of its kind and offers many advance features like getting WhoIs-informations about the host.
*Block outgoing TCP & UDP connections selectively, with port-specific-blocking *Shows you the hostname for the connection
*Can provide you with WhoIs information
*Block connections of apps when you are on a cellular network
*Block analytic providers / data collectors which PrivaCy cant
*Block unneeded content (Ads), iAd, Admob...
*Easy to use interface & control app and many more .
!Available via Cydia and RockApp for just $2.99!
If you don't know about Firewall iP:
Firewall iP is the only security app of its kind and offers many advance features like getting WhoIs-informations about the host.
*Block outgoing TCP & UDP connections selectively, with port-specific-blocking *Shows you the hostname for the connection
*Can provide you with WhoIs information
*Block connections of apps when you are on a cellular network
*Block analytic providers / data collectors which PrivaCy cant
*Block unneeded content (Ads
), iAd, Admob... *Easy to use interface & control app and many more .