title: How to Programmatically check and open an existing app in iOS 8?
body: <p>I want to check whether an app is present in my iphone or not. If it is present I want to launch it else open the App Store link of the app.</p>
  
  <p>Please suggest the required parameters to do so and way to implement it.</p>
  
  <p>I have the App Store link to open the app but I need to check if app is already present in the phone.  </p>