Shoppers returned to malls on Sunday after they were allowed to reopen following the improving situation of the coronavirus outbreak in the country.
They are required to load the Thai Chana mobile app to their mobile phones for check-in and check-out at shops.
The app has been created to collect visitor records in shops and also provide details such as opening hours and visitor limits among others.
Shops are also required to register with Thai Chana.
The registration for shoppers caused a long line at some malls, including Siam Paragon, as many shoppers wanted to be among the first to go inside when it opened.
The Centre for Covid-19 Situation Administration said on Sunday more than 26,000 shops, most of them in Bangkok had registered with Thai Chana and 4,635 people were checking in with it every minute.
Shops that were popular on the first reopening day included Ikea at Megabangna, which on Sunday afternoon stopped admitting new visitors as the number reached the reduced capacity. Other malls were less crowded.
Shopping centres had been closed for at least a month, depending on their location, leaving only supermarkets allowed to operate.
Patcharee Chobdee, an owner of a mobile phone shop at Big C in Ubon Ratchathani, hoped that her business would return to normal after the store was closed for one month.
“I had to sell my products at my house with a discount of more than half of the price tag to get money,” she said.
“I am still not sure how the business will go from today,” she added.
The government decided to allow stores and some businesses to reopen after the number of new Covid-19 patients and fatalities slowed to a trickle.
The country recorded three new infections on Sunday, with no new deaths.
Malls are required to close at 8 pm so that people can get home before the curfew starts at 11 pm.