I have been using a free messaging service from Asia. It is promoted as "the ideal combination of SMS, Twitter, Facebook, Skype and Instagram." With over 235 million users a month. It's called "WeChat," it is a communication app from a Chinese company.
Even though the WeChat user interface is not easy to grasp initially, you will eventually get accustomed to using it. It is also available for many mobile platforms and PCs with android emulator software installedl. It can be used on Blackberry, Symbian and Windows devices. The good thing is that it is a free app that has much functionality and (for now) no ads.