Unable to fire an intent to applications

How to fire an intent from an activity to inbuilt applications in android? Am writing an application where i can set a shortcut key to the applications. Am able to save the key and other things. but how t开发者_如何学JAVAo launch that application from this activity? How to Fire an intent to inbuilt apps in android like Calculator, messaging etc..

this question was asked a while ago.

How to get a list of installed android applications and pick one to run

there is an answer to your problem

You can bring calculator infront.see here