App developer Steven Troughton-Smith recently dug into the firmware of Apple's (NASDAQ:AAPL) upcoming HomePod smart speaker. That digging apparently revealed a bunch of information about Apple's hotly anticipated premium iPhone model.

Troughton-Smith posted his findings to social media (via MacRumors). Let's go over them.

Apple's iPhone models in a "mosaic" pattern.

Image source: Apple.

The display question answered

A while back, generally reliable analyst Ming-Chi Kuo with KGI Securities published some information about the display of the upcoming iPhone. The analyst was among the first (if not the first) to describe the display of the upcoming iPhone as a full-face OLED display with a "notch" at the top.

Troughton-Smith found the following image inside of the HomePod's firmware, presumably depicting the iPhone 8:

Kuo's description of the device appears to have been accurate; the illustration of the new iPhone found in the HomePod's firmware matches up perfectly with his description. 

That's not the only thing that Kuo got right, either. 

Kuo previously published the display resolution of the OLED display that would be used in the iPhone 8, he revealed that a portion of the display would be used as a dedicated "function area." 

Kuo even published the size and pixel resolution of the non-function area portion of the display. 

Per Troughton-Smith's findings, Kuo appears to have been correct. The HomePod firmware doesn't mention the display resolution of the full display, but it mentions a display resolution of 2436 pixels by 1125 pixels -- exactly the pixel resolution that Kuo published. 

Kuo also said that the usable area of the display would be 5.15-inches. That claim can't be confirmed by the leak directly, but considering that Kuo nailed the resolution and the other bits, I view this as a verification of Kuo's report. 

Touch ID out, Face ID in

Apple had been rumored to be trying to embed a Touch ID sensor underneath the OLED display in the upcoming iPhone. Recent reports, however, suggest that, at best, Apple is still struggling to get the feature implemented, and that at worst, Apple has simply dropped the feature altogether

Per Troughton-Smith, there's "nothing" in the firmware "to suggest an ultrasound under-the-display Touch ID here." 

Although there's still a possibility that Apple could add the feature in and that it might be exposed in a future HomePod firmware update, Troughton-Smith's findings definitely have me doubting that the under-the-display Touch ID is happening. 

Apple's iPhone 8 is also rumored to have a facial recognition system that, per Bloomberg, is intended to ultimately supplant Touch ID. 

Troughton-Smith tweeted that he found evidence in the HomePod firmware that "reveals the existence of upcoming iPhone's infra-red face unlock ..." 

Foolish takeaway

Although much of the information about Apple's upcoming iPhone had been leaked via supply chain rumors, anonymous sources, and so on, this direct confirmation straight from Apple's code is really interesting. 

All that's left for Apple investors at this point, given the sheer volume of these leaks, is for Apple to launch the devices, announce the price points, and then get these devices into the hands of consumers. 

It'll be very exciting to see how it ultimately does. 

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.