1. Viber
Viber lets everyone in the world connect. Freely. Millions of Viber users call, text, and send photos to each other, worldwide- for free
2. Whatsapp
WhatsApp Messenger :: cross-platform mobile messaging app for iPhone, BlackBerry, Android, Windows Phone and Nokia. Send text, video, images, audio.
3. TuneIn Radio
Listen to the music you want to hear with Play Me, a constant stream of music created just for you. Use Thumbs up and Thumbs down to tell us what you like so that your mix gets better and better every time you play. It’s like having your own personal radio station.
Also includes the features you know and love – my music, mp3 store, create a mix, gigs and offline playback – so that you can store your favourite mixes on your phone and enjoy anywhere, even without a connection.
Exclusively for Nokia Lumia
6. Instagram
Capture and Share the World's Moments. Instagram is a fast, beautiful and fun way to share your life with friends and family.
7. Skype
Skype is one of the best communication apps around. Make free Skype-to-Skype video and voice calls, and send instant messages to friends and family wherever they happen to be using either your Wi-Fi connection or 3G mobile internet.
8. IMDb
IMDb is the world’s largest collection of movie, TV and celebrity information. The app makes it easy to find showtimes, watch trailers, browse photo galleries, find the latest DVD and Blu-ray releases, and share movie information.
9. Foursquare
Foursquare helps you find the perfect places to go with friends. Discover the best food, nightlife, and entertainment in your area.
10. TripAdvisor
Helping travelers plan and have the perfect trip. (Restaurants, Hotels etc)