All over China , you will find this logo in stores
You pay by scanning a QR code at the cashier
They are welcome in restaurants
Machines in McDonalds accept them
They are accepted in stores
In the GAP
Miniso, my favorite japanese shop for small items like earphones, sunglasses , bluetooth speakers & umbrellas
This barber shop does not accept cash, only Wechat & Alipay
You can use them also in vending machines
You even get discounts using them in the supermarket
you can load your Shangahi transport card
https://www.travelchinaguide.com/cityguides/shanghai/transportation/
You won't need to bring cash here if you have your phone