1. Build and run your application on the device as described in "Running Applications"
2. Launch Instruments.
The Instruments application is located at <Xcode>/Applications. (<Xcode> refers to the installation location of the development tools.)
3. Choose a template, such as Activity Monitor, to create the trace document.
A trace document contains one or more instruments that collect data about a process.
4. From the Default Target pop-up menu in the toolbar, select the iPhone OS–based device containing the application from which you want to collect performance data.
5. Add or remove instruments from the trace document to collect the desired data.
6. Use the Default Target pop-up menu, to launch or attach to the target application.
7. Click Record to start collecting data and use your application, exercising the areas you want to examine.