Free apps for messaging

Viber

Viber combines the best of rival services such as Skype and WhatsApp. It's free, and allows you to send messages and make calls for free to other Viber users.

Aber requires your phone number and an activation code to get started, then scans your contacts list to see if any of your friends are using the service. You can then send messages to individuals or groups, and make calls (although there's a charge for ringing non-Viber users from the app). The call function, plus a cleaner experience, puts Viber ahead of WhatsAppr but its worth keeping track of storage and data consumption - voice messages, calls and conversation threads can quickly gobble up your space and allowance.

WhatsApp

WhatsApp is the Android and iOS answer to BlackBerry Messenger, allowing you to send notes to friends or groups of friends at no (or little) cost. The app is free to use for a year, then requires a small annual subscription. It's hugely popular, so ifs likely a good chunk of your contact list will already have WhatsApp, making it a cheaper way to send video, picture and intern.ational messages than SMS.

GroupMe

GroupMe offers similar goup messaging features to WhatsApp - but it offers one advantage, despite its smaller userbase. The service is owned by Skype, which means its Windows Phone app is updated at the same pace as the i05 and Android versions. It lacks some of their features, but GroupMe may be a good option for Windows Phone users waiting patiently for other apps to update.