When you have enough privileges on a channel, you'll have the need to promote users, kick them, ban them, etc. AndroIRC let you do all this things very easily. All you need to do is bring the users list up (see Useful shortcuts).
You can now show a context menu for each user clicking on a nick. A context menu will let you kick, ban, promote (under privileges), ping, etc. Easy, no?
By long pressing on the user, you can quickly insert the nickname into the edit text.