Android 4.x has vpn, so one way to sniff data is to setup openvpn and on your server tcpdump or wireshark everything.
To sniff 3G/GSM I believe one would have to root their phone and sniff it there as most people dont have 3G/GSM hardware. I dont know more about that, perhaps its as "easy" as rooting it and running tcpdump on the device and saving to sd-card from some of its interfaces?
Android 4.x has vpn, so one way to sniff data is to setup openvpn and on your server tcpdump or wireshark everything.
To sniff 3G/GSM I believe one would have to root their phone and sniff it there as most people dont have 3G/GSM hardware. I dont know more about that, perhaps its as "easy" as rooting it and running tcpdump on the device and saving to sd-card from some of its interfaces?