There are a number of apps available for smartphones, including those that run Google's Android operating system, which utilise the handset's Wi-Fi and 3G connection to send messages, pictures, video and voice clips to other smartphone users. This can potentially save you money, as if you have unlimited 3G or Wi-Fi in your mobile phone package, you can utilise this in place of traditional text messages which your operator will charge you for. Many of these are cross-platform as well so you're not restricted to only talking to friends that have the same type of phone as you. Here's five of our favourite free messenger apps for Android.
Working across Android, BlackBerry and iPhone, PingChat. lets you send text messages, photos, videos and voice notes, all using your data or Wi-Fi connection rather than you SMS allowance. There's also support for group conversations.
Similar to the other messengers we've listed here, iGotChatMessenger offers a 'poke' feature similar to the one seen in Facebook. It only works on Android and iOS devices however.
Similar in look and feel to RIM's BBM that only works on the BlackBerry platform, LiveProfile is another cross-platform messenger that will ensure you can message friends on Google Android, iOS and BlackBerry devices.
Kako Talk Messenger
Kako Talk Messenger is another similar messenger service that uses 3G or Wi-Fi to send multimedia to other smartphones featuring the app. It works on Android or iPhone and even has emoticons that work on both platforms.