If it's an iPhone, hold your finger on the Ask icon until it starts to jiggle. At that time, you'll see a little red X in the corner of the icon. Touch the X to delete the app. Then press the round "start" button at the bottom of your phone and the other icons will stop jiggling. Be careful not to touch any other icons once they start jiggling, so you don't accidentally delete an app you want to keep.