Nike+  for iOS received an update that makes it even more social with group challenges and chat. Aside from leader boards with other runners, the new challenge feature allows users the ability to competitively challenge their friends with distance and speed goals. Those who are using the challenge mode have access to a group chating feature to either trash talk to your opponents or, at the very least, be the nice person and encourage runners in real time. The update is also expected for Android soon.

What's New in Version 4.3
INTRODUCING NIKE+ CHALLENGES

Ready to take on your friends? With Nike+ Challenges, you'll compete with your friends and motivate each other to go farther and faster than ever before. Track your progress, top the leaderboard, and snag a medal. Every run counts.

• Choose a distance and invite your Nike+ friends.
• Keep track of who's in the lead and stay motivated through group chats.
• Finish a Challenge before your friends and take home a medal. We'll leave the bragging rights to you.