There’s an “Offers” tab where the latest promotions are kept, and you need to tap on the promo and “Save to card” so that you are eligible for the promotion. That’s how simple!
I was just browsing through the app the other day when I realise I had not utilised this promotion! If you are like me, you still have 4 days more (expires 16/12/18) to participate in this promotion where you need to be amongst the first 20000 cardmembers (still available at time of writing!) and save your AMEX credit card to your mobile wallet so that you can pay through Apple Pay, Google Pay or Samsung Pay.
For instance, you can get an apple pie from McDonalds or even a bottle of water from Giant, and you will receive the $1 cashback the following working day.