How do I connect a Fitbit to this app?

http://community.myfitnesspal.com/en/discussion/10098937/faq-syncing-logging-food-exercise-calorie-adjustments-activity-levels-accuracy#Item_30

Connect your accounts at http://www.myfitnesspal.com/fitbit

Set your goal to .5 lb. for every 25 lbs. you're overweight: http://www.myfitnesspal.com/account/change_goals_guided

Enable negative calorie adjustments: http://www.myfitnesspal.com/account/diary_settings

Ignore your Fitbit calorie goal and follow MFP's, eating back your adjustments.

You can learn more in the Fitbit Users group: http://community.myfitnesspal.com/en/group/1290-fitbit-users