When drivers can finally refuel at service stations, they are only allowed to buy 20 liters of gasoline, or about 5.2 gallons.
"This will not last me long," said Ariel Alonso, a businessman who refueled Monday at the El Riviera gas station.
"I have to leave a reserve of five liters in case anyone gets sick at home," and has to be taken to the hospital, he said.
The Ticket app is run by XETID, a state owned software firm. Last week, the company's commercial director Saumel Tejada, told news site Cuba Debate that more than 90,000 drivers had sought refueling appointments using the app.
Ticket has been around for three years, and was previously used by Cubans to secure appointments at notaries and at gas stations where they could pay for fuel in local currency. But now it is almost the only way for drivers to get their cars refueled - without going to the black market.