Is it possible to communicate between two android phones?

Question

I already read following question and answers.

How to communicate between same application installed on two android handset?

I think the use case is totally same as mine.

But I still have a remaining question - what does 'using internet' in the article above mean between two phones each far away?

I think I need some more explanation in detail.

Thanks in advance.

Answer 1

Yes, two applications can talk over the internet (or bluetooth or sms/mms for that matter, but less practical). Just like any two computers can communicate over the internet. There's a wide variety of protocols. A whole world really. Do you need references to some tutorials on networking or am I totally missing your question?

EDIT: You can try The TCP/IP Guide for an intro

EDIT: And for android you probably want to use their socket interface

UPDATE: About how to communicate between clients - you probably don't want to rely on knowing a particular peer's IP address. Usually what you do is work with some known host as a server, which coordinates between the peers, sometimes relaying the messages between them, or alternatively just notifying the clients about each other's addresses.