The highly anticipated launch of the two new iPhone models is expected to mount a fresh attack on the high-end smartphone market in Thailand.
Apple's iPhone 5C is seen retailing in Thailand at 19,000 to 21,000 baht for the 16-gigabyte version, while the iPhone 5S model would retail at 27,900 baht.
Nokia, whose handset division was just bought by Microsoft, is set to roll out a high-end Windows Phone model, the Lumia 1020, in October for 24,990 baht.
Sony and LG plan to introduce high-end Android smartphones for 20,210 and 19,900 baht respectively. Samsung will launch its Galaxy Note 3 at a price topping 20,000 baht.
Jarit Sidhu, senior market analyst at IDC Thailand, said competition in the local high-end smartphone market looks set to intensify in the fourth quarter as new products debut.
He said the country's economic slowdown will have a limited effect on the market for smartphones, which tend to be bought for emotional reasons. In addition, the festive fourth quarter is the most dynamic period of the year.
In IDC's view, the new iPhones will help Apple's iOS maintain its second-place ranking in the Thai market with a 20% share. The Android operating system controls 50% of the market here.
Apple recently slashed the price of the iPhone 4S 8 GB to 14,900 baht in a bid to expand upcountry.
Mr Jarit predicts that other handset makers will follow suit with price cuts to compete with Apple.
IDC is maintaining its full-year forecast for Thai smartphone sales at 9.3 million units, with high-end models contributing 32%.
Opas Cherdpunt, the managing director of M Vision, an organiser of Thailand Mobile Expo, said next month's event will see fierce competition as the two new iPhones join the battle with other global handset makers.