However, many users of Terminal Emulator for Android want to run command line programs that do these things. Of course, most consumer Android devices don't have root access enabled by default, so you may not be able to use the 'su' command on your device. You may need to become 'root' in order to gain permissions to run some commands. It could mean that the command exists, but you don't have permission to run it. The Android shell will print 'permission denied' when it just can't find the command, instead of a more accurate error message like 'command not found'. It might simply mean that you have misspelled the command name, or are trying to use a command that is not installed on you device. I use 'developer' edition Android phones that don't need to be rooted, and I don't have any interest in hacking phones.
I've written a brief, incomplete, guide to using the built-in Android shell: Android Shell Command Reference. If you don't know what all that means, and why it's cool, then this probably isn't the program for you. This lets you run various Linux command line utilities. It is useful for accessing the Linux command line shell that is built into every Android phone. A terminal emulator is a program that makes your Android phone act like an old fashioned computer terminal. Unfortunately Google Play does not allow applications that start with the word 'Android'. The name was changed due to Google Play branding guidelines.
