Now playing: Watch this: The Kevo Plus unlocks the smart deadbolt's full potential

LAS VEGAS -- The Kwikset Kevo Smart Deadbolt is set to get a substantial upgrade in 2015, with a new "Kevo Plus" router hub that'll bring remote locking and unlocking into the mix, along with unlimited eKeys and real-time activity monitoring. There's a catch, though -- Kwikset is launching Kevo Plus as a premium service upgrade, complete with fees you'll need to pay in order to enjoy the new features.

That's a disappointing move, and a bit of a head scratcher given that competing products like the August Smart Lock and the newly announced Yale Real Living NFC Deadbolt offer similar features without charging any sort of service fees.

Tyler Lizenby/CNET

Of course, Kevo users don't have to upgrade to Kevo Plus, and can still enjoy the product's convenience-minded touch-to-enter feature without paying any fee at all. Still, charging a fee for full smart lock functionality feels like an arbitrary move, and a stingy one at that.

The Kevo Plus Gateway plugs into your home's router, acting as translator between the lock's Bluetooth LE signal and your home's Wi-Fi network. With Kevo Plus, you'll be able to lock and unlock the door from anywhere in the world using the Kevo app.

Users who upgrade to Kevo Plus will also be able to create and distribute an unlimited number of eKeys, which allow others to open the lock. Those eKeys can be set to provide full, unfettered access, or they can include schedule restraints.

Currently, UniKey offers Kevo owners unlimited "Guest eKeys" that expire automatically after 24 hours, and charges $2 for each permanent "Anytime eKey," or eKeys with specific schedule constraints.

Tyler Lizenby/CNET

The Kevo Plus is due out in spring of 2015, and while the specifics of the service charge are yet to be finalized, Kwikset tells me it'll be somewhere around $50 per year. Additionally, users who sign up for a year of service will get the Gateway at no upfront charge.

Moving forward, Kwikset plans to add scheduling features that will allow users to set the deadbolt to automatically lock or unlock at certain times, along with lock grouping for homes with multiple Kevos installed.