Apple's 2015 WWDC - Playing catchup, I vote I like the idea for Mac OS Ten Eleven and iOS9

[N-OS X-tasy!]

There are many parameters to consider when evaluating the success of Apple Pay, Nathan. A few are listed below:

• User adoption rate
  
• Vendor adoption rate
  
• Total volume of transactions processed
  
• Growth rate of transactions processed
  

I concur with sekker that Apple Pay's adoption rate, particularly by vendors, has been amazing. Notably, vendors have been much more vocal in their efforts to publicize their adoption of AP than they ever did for AP competitors.