If you want to have an access to a command line prompt or Terminal Window on your iPod touch or iPhone, the following might be a good instructions for you but firstly your iPhone must have been jailbroken

1. Go to Cydia and launch it on iPhone’s Springboard.
2. When you have openned Cydia press to chose the Sections tab on the bottom screen
3. Now you need to chose Terminal Support on the Sections list
   On Packageslist choose MobileTerminal.
4. Press the Install button at the top right of the screen.
5. Look at the screen top right side and find Install button then press it!
6. You will be asked whether to cancel or confirm the installation thus click confirm to begin installation
7. Wait the installation to be completed after it’s completed then click on Close Window button
8. Return to Springboard by clicking HOME. You’ll see the new MobileTerminal icon there, to launch the app, PRESS IT!
9. Done, now you have a command line prompt (Terminal window) on your iPhone or iPod touch.

Hope you’ll find this post useful and see you in the next post!