Apple has tasked its top supplier, Foxconn, with producing two different prototype designs for a foldable iPhone.

Foldable phones are considered the next evolution of modern smartphones. Foldable designs allow for phones that can more easily be carried in a pocket, yet expand to offer the screen real estate of a small tablet. While Microsoft, Motorola and Samsung have released foldable phones, Apple has yet to embrace the trend. Many believe Apple has been working to perfect the design and avoid the problems other companies have faced.

Apple’s plans may be closer to fruition, if the rumors are to be believed. According to TechRadar, citing Taiwanese website United Daily News, two prototype designs have passed the necessary durability tests to be considered for production.

One design is evidently the traditional clamshell style, such as those sold by Motorola and Samsung. The other design is reminiscent of the Microsoft Surface Duo’s dual-screen design. It’s unknown whether Apple will eventually release both designs, or consolidate around a single one.

Obviously, Apple testing foldable designs doesn’t provide a lot of concrete information, but it’s further evidence that Apple will likely enter the market once they are convinced they can do so with their usual panache.