How to auto increase timer

How to auto increase timer

So I have this button grid 
On each button there is a timer on the top right in the form mm:ss however I dont how to auto increase all 9 buttons at the same timer, I'll also be adding in some more buttons dynamically via ajax so I need the method to work for any added button. I'll also add that the buttons are being removed from touch so the timer cant be for inviduvial buttons, if that makes sense