There are no shopping opportunities in Iraklia Cyclades, except for a couple of grocery stores to buy food and beverages. Otherwise, there are no other stores on the island. For more shopping, the residents go to the neighbouring island of Naxos, which is only 1 hour by ferry far.
Have in mind that credit cards are not accepted on Iraklia. Moreover, there are no banks, except for an ATM. More banking deals are done in Naxos.