This is on of those tips that is usually hidden until you accidentally stumble upon it. If you make a call using your phone, you can quickly redial the previous number by pressing the big green dial button. This will load the previous number into the phone field. Press the green button again and you are dialling. A quick tip but hand if you need to re-dial.
Hit the big green button to re-dial.
A quick tip, but not one you would normally come across.