For both Android and iOS, Pebble developers can now add two-way communication to their applications for their watchapps through Pebble's SDK, PebbleKit. The AppMessage API enables Pebble watches to send and receive data from smartphone apps for remotely controlling internet connected devices, receiving scores from your favorite sports teams, and checking in with apps like Foursquare or Facebook. iOS developers utilizing two-way communication, however, will need to have their apps whitelisted through Pebble as a part of the Made For iPhone program. In the future, Pebble plans on making that part of the process easier for iOS devs.
You can find all the details about Pebble's developer updates, latest firmware, and new watch colors on Kickstarter.