Surface Dial in action. Image source: Microsoft.

It's been a pretty busy week in the world of consumer tech. Both Microsoft (NASDAQ:MSFT) and Apple (NASDAQ:AAPL) hosted product events this week, showcasing a wide range of desktop and laptop PCs. 

The software giant jumped into the all-in-one (AIO) PC space with Surface Studio, challenging the iMac in wooing creative professionals. Microsoft also offered some incremental updates to the Surface Book. Apple took the wraps off its expected MacBook Pro refresh, and the event was mostly in line with expectations. (Who didn't expect Apple to unveil the thinnest and lightest notebook it's ever made?)

But the real storyline beneath the headliners were two subtle plays at improving user interfaces, each in their own way: the Surface Dial and the Touch Bar.

An evolutionary interface

The importance of interface innovation cannot be overstated. Interfaces utterly and fundamentally define how we interact with our gadgets. Think about the original graphical user interfaces from the 1980s, or the modernization of touchscreen interfaces from the 2000s. These marked profound paradigm shifts in computing. While neither Surface Dial or Touch Bar will be as revolutionary, they are certainly incremental and have potential.

Surface Dial is very much catered toward creative use cases. It can be placed on a Surface device, and creates a contextual tool wheel or offers another way to physically interact with a touchscreen. When placed on a desktop, the uses seem more negligible. It's not like we're lacking for a way to scroll.

Touch Bar changes dynamically depending on the context. Image source: Apple.

Touch Bar, on the other hand, appears to be much more versatile in everyday use. It's the exact same idea that Apple had with the original iPhone. Instead of fixed physical buttons, virtual buttons on a touchscreen can be nearly infinitely adaptable depending on the context and the application -- and the developer's imagination. 

But at what cost?

Surface Dial has a cost advantage. The small puck-like device costs $100, and is compatible with a wide range of Surface devices. You don't necessarily have to buy the $3,000 Surface Studio to use it. On the other hand, Touch Bar comes at a $300 premium on the new MacBook Pro (compared with the model that includes standard function keys).

As we saw with Apple's initial push into Retina Macs in 2012, the cost of adoption is quite important. It wasn't until the premium fell that consumers began to adopt high-resolution displays en masse. The real coup would be if Microsoft expanded Surface Dial support throughout its broader OEM base. The software is already there, so it should just be a matter of including the necessary hardware. 

Still, Touch Bar seems to have a lot more potential to improve utility across a wider range of use cases, and the cost will inevitably come down over time. Considering Apple's penchant for bringing new innovations to laptops before desktops, it will presumably work to somehow bring Touch Bar to desktop Macs eventually, perhaps in the form of a new stand-alone keyboard that includes a Touch Bar.

I'd bet on Touch Bar to emerge as the real winner over time.

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.