how do i delete a previously purchased app

finger on app icon until it wiggles and then tap on 'x' and then tap home button to stop wiggling

also go to itunes and highligt apps and delete it from there

Tap and hold the app icon on your phone until it wiggles, tap the black X to delete. Then in iTunes on your computer, click on the Apps folder under Library on the top left, right-click on the app in the window to the right, choose Delete. BTW, the app store will keep track of the fact that you have previously purchased this app anyway so you can redownload it in the future if you wish (assuming it's still in the app store).