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. Maybe a bit easier to use (and it works on WPA2!).

*** ROOTED PHONE *** is required. Please note that if webuser uses SSL this application won't work.
This application due to its nature is very phone-dependant so please let me know if it won't work for You

Use with stock browser (might not work with other)
Legal notice: this application is for educational purposes only. Do not try to use it if it's not legal in your country.
I do not take any responsibility for anything you do using this application. Use at your own risk