Octopus Cards are stored-value electronic cards which are accepted in Hong Kong as a form of payment to most public transportation (not RED mini bus), convenience stores, fast food shops, supermarkets, and vending machines.
There are various types of Octopus cards but you can choose from the 2 options below:
Sold Tourist Octopus
$39 with no initial value
No deposit required and non-returnable
Card type: Adult only
Can be bought at convenience stores (7-eleven, Circle K, Vingo) and branches of China Travel Service Hong Kong
You can recharge the stored value easily in convenience stores and MTR customer service centres in the city