Mode of Payment in Hongkong and China

We will be going to hong kong and china next month tapos first time namin na mag hk and china. Ano ba usually ginagamit kapag may bibilhin ka doon like foods, transpo, souvenirs sa hk and china? Gumagamit parin ba sila nang cash? Kase I've heard na cashless ang china like gcash, alipay etc. Please send us tips.