How to make camera start faster
Try InstaCamera Pro from Google Play Store. It starts very fast and has preferences to start camera and takes photo just by a single touch from home screen of your phone:


  InstaCamera is the quickest way to take a photo with your phone. 
  
  There's no long process: just press the widget and it takes a photo, then closes just as quickly.


The paid PRO version is supposed to be faster than the free version.