Ranked in these QuestionsQuestion Ranking
Pros
Pro Keeps track of segments without user manually timing them
Segments - can track your improvements or compare with friends, club members without manual input. Or you can keep them private.
Pro Accurate distance measurements
Pro Allows challenging other people
You can set a goal and challenge friends as well as local professional athletes.
Pro Can share running routes with others
Running is boring if it's the same stretch of road. Stava lets you share good places to run.
Pro Supports multiple devices
Current list includes:
iPhone 3GS and later,
Android 2.2 and later,
Garmin Forerunner and Edge,
Soleus,
Timex Run Trainer 2.0
Pro Equipment tracking
This lets you figure out how many miles you've put on a pair of shoes before it's time to get a replacement pair.
Pro Watch the pros
You are able to follow some professional athletes and see their training etc.. Makes you realize how hard they train.
Pro Tracks heart rate with chest strap
Can also track heart rate with other types of HR monitors e.g. arm strap or smart watch.
Cons
Con Not for indoor spinning or gym workouts
Con No interval training!!!
Con By default, all your GPS data is made public
From their blog:
"The basic level is to choose to not use any privacy controls and make your info available publicly..."