How to send messages from android app without using phone carrier service

I want to send.messages from my app without using phone carrier charges.

Without phone carrier you mean sim card?.. cause if not there a lot of apps now that gives free text try visit this link

I want to achieve this functionality in my app…i want to send free messages from my app which i am going to develop.

Looks great idea hope you’ll got the things you want to do.

Thanks but i still didn’t get any idea how to do this