Apple will have limited iPhone Duo units available in stores on Friday

​Online order ⁠pickup and limited walk-in purchases will be available in the US, Australia, Canada, Mexico and the UK

Apple has said it will ​have 'limited' numbers of its folding iPhone Duo phone available ‌for walk-in customers when the device launches on Friday, after initial online orders sold out in minutes and pushed delivery times for some customers to January.

Apple announced ​its first folding phone in September, with analysts expecting it ​to quickly come to dominate a niche segment where ⁠rivals such as Samsung Electronics and Huawei Technologies have sold premium ​offerings for years.

But the iPhone Duo is also a more complex ​product than standard candy-bar iPhones, with a tight-fitting hinge that analysts believe may take time for Apple to learn to manufacture in high volumes.

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“On Friday morning, our ​teams look forward to welcoming customers at Apple Stores to ​experience iPhone Duo and the incredible iPhone line-up for themselves," Apple said in a ‌statement. "Apple ⁠Stores will have limited iPhone Duo available for walk-in customers, and we’re working hard to get this revolutionary new product into customers' hands as quickly as possible.”

The availability of walk-in units will vary by ​country, Apple said. ​Online order ⁠pickup and limited walk-in purchases will be available in the United States, Australia, Canada, Mexico and much ​of the UK and Europe.

But other regions will only ​have ⁠iPhone Duo units available for customers who already bought them online. Those include mainland China, France, Hong Kong, India, Japan, Malaysia, South Korea, Taiwan, ⁠Thailand ​and the UAE, Apple said.

In the China-governed territory of ​Macau, the iPhone Duo will be available for walk-in customers only, with limited inventory, ​Apple said.