The battle of the ecosystems: Apple, Google, Microsoft, & Amazon.com — by Daniel Christian with thanks to Krista Spahr, Michael Mandeville, Bill Vriesema, and Adam Tozer from Calvin College for their feedback/inputs on this.

 

BattleOfTheEcosystems-DanielChristian-August2013

PDF version here [1.35MB]

 

 

Also see:

 

Ecosystem value metrics

 

Ecosystem value metrics - developer perspective

 

Addendums on 8/13/13: