Rootless CLI Utilities
You don't need root.  You also don't need a terminal, for an app to use its own private utilities.  But if you want vim, Terminal IDE provides that, a number of other utilities (git, ssh, tmux), the ability to use bash or Java as a 'scripting language' at the terminal, and the ability to create and install Android apps on-device.  I use Terminal IDE and vim quite a bit, (but with Better Terminal Emulator Pro's terminal, actually.)