So the pid is 717. Yours will probably be different.
Start debugserver on the device, and attach it to the Calculator process by using its pid. I’ve used port 1234, but it could be anything greater than 1024:
JB-phone:~ root# ./debugserver *:1234 --attach=717
Attaching to process 717...
Listening to port 1234 for a connection from *...
The debugger is attached to the Calculator process, now let’s attach lldb to it from your Mac:
start lldb on your Mac
platform select remote-ios
process connect connect://192.168.1.20:1234
where this is the IP address of the device, and the debugserver port
Notice that lldb says the process has been stopped. It really means “suspended”, as if it were at a breakpoint. Tap buttons on the Calculator app - they won’t work, proving that the app is paused.
We can unpause the app by issuing the continue command to lldb:
Process 717 resuming
… and you’ll see the app has resumed, and buttons work once more.
If you want to continue using lldb, then do so - there’s a ton of information on the lldb homepage. In the next instalment, we’ll switch tools and use Jay Freeman’s Cycript to play with this app some more.