With a good interface and useful functions, Chat it Out is one of the best messengers in Android.

First of all, you need to register for a new account. It does not require user contact list to find other users. I guess that some users may not like the use of his/her private contact list. Instead, Chat it Out has its own user list.

The user list shows all users on the chat server, you can find any new partner to chat with. Just click on a user.