RunKeeper displays your route using Google Maps and tracks distance, duration, speed, pace and calories burned. You can also input your runs manually (useful when running on treadmills) to add them to your "workout logs".
Earn points, unlock achievements, take on challenges and quests and level up. Seeing progress, getting rewarded for activities and reaching a set threshold feels nice and helps in continuing to be motivated. Especially when just starting out. There's even a leaderboard so you can compare your...
Endomondo displays your route using Google Maps and tracks distance, duration, avg. speed, avg. pace, calories burned and hydration. It even tracks what music you listen to while exercising (can be viewed on their website).
Lark feels like a friendly personal trainer that chats with you every day to log your exercise and meals, while providing semi-automated responses. It's easy to use and feels like having a conversation instead of filling out a form.
While Lark recognizes simple dishes like pasta and understands various vegetables, cuisines like Chinese and Indian won't have any dishes that get recognized by Lark. Users will have to resort to trying to fit their meals into cookie cutter ingredients and the closest substitute.