A U.K. smartphone case maker, Design My Case, said it already know the physical size of the yet-to-be-announced Apple iPhone 13. The case seller has revealed a photo of an iPhone 12 fitted inside a supposed iPhone 13 Pro case along with another iPhone 13 case.

If it is true, the we can expect the same design as iPhone 12 with pretty much the same dimensions. However, it is noted that that the case has a large cutout for the camera module. With regard to this, Design My Case said it expects a camera upgrade.
The case maker also mentioned that the new iPhone will be slightly thicker by about 0.2 mm over the existing model. An increase in the camera bump is also expected from the Pro and Pro Max models.
The company is so confident of the sizes of the new iPhones it has reportedly confirmed stock for the new cases. Though, the company has not gone to the extend of offering the case at this point.
Images: Design My Case.