how to debug a running application in android?

Generally, we can launch an android application in two mode 1) Running and 2) Debugging. While running an application, it works fast, faster speed allow developer to navigate android application smoothly. But while launching in debug mode, its comparatively slow. So i was searching to find a way to launch application in run mode and whenever i want, switching to debug mode. Finally i did it. so lets see

It contains only two steps

1) Launch your application in run mode , and do whatever you want to do

Step 2) Open the DDMS tool, select your device and then select your application package name of application for which you want to change the mode. And click on debug. See Screen shot