Will Siri work with 3rd party apps after update from iOS 9 to 10? I want to purchase iPhone 6s having iOS 9. I will update from iOS 9 to 10 but I want to know if after updating the iOS version Siri work with 3rd party applications or not? Are there any changes in Siri features in iPhone 6s to iPhone 7? I want to work with 3rd party applications using Siri in iPhone 6s. Is it possible?
SiriKit, or third-party integration with Siri, is available on any device compatible with iOS 10. According to Wikipedia: 


  Siri is compatible with third-party app-specific requests, such as starting workouts apps, sending IMs, requesting the Lyft or Uber apps or to use payment functions.


Note that not all apps utilise SiriKit, and only those that do will work with Siri.