FaceNiff is an Android app that allows you to sniff and intercept web session profiles over the WiFi that your mobile is connected to.
It is possible to hijack sessions only when WiFi is not using EAP, but it should work over any private networks (Open/WEP/WPA-PSK/WPA2-PSK)
It’s kind of like Firesheep for android. Your phone must be rooted to use this program.
Originally it started off for just Facebook but the author has added support for these other sites: FaceBook,Twitter,Youtube,Amazon,Nasza-Klasa