Skype for Symbian

From Skype:

Call and instant message Skype contacts free -- wherever you are. If you already use Skype on a computer, you'll see your full contact list when you sign in to Skype on your Symbian phone. Call free Skype-to-Skype on your mobile, and send and receive instant messages (IMs) one-to-one or with a group. Call and text people who don't have Skype at really low rates. It's especially great value if you're calling or texting people who live abroad. Simply dial the number in Skype and pay with Skype Credit or talk unlimited with a subscription. When you're abroad, connect to a WiFi zone and avoid roaming charges on calls and texts. This applies to Skype-to-Skype calls, plus calls and texts to phones. Share pictures, videos and other files. It's also free to send and receive pictures, videos, and other files so you can share your experiences and stay in touch when you're away from a computer. Take a picture with your built-in camera and send it to friends on Skype. Easy peasy.