Apple has been cagey about its Apple Watch sales numbers, which it refuses to disclose beyond a vague "they're good". Either way, the company might be planning to bring something more unique to the table with future iterations of the Apple Watch sporting some interesting design changes in a newly-granted patent.

According to the filing, the next iteration of Apple's premium wearable may come complete with a special watch strap featuring modular electronic components that can be swapped out according to the tastes of the owner desires. These would be contained within the watch strap links, with the idea being that users could remove "dumb" links from the Apple Watch 3 and replace them with modules that contain blood pressure monitors, cameras, speakers or additional storage.

Specifically, Apple's patent describes "a band system, comprising a wearable device and multiple modular functional band links, each comprising an electronic component and a pin operative to electrically and mechanically connect its modular functional band link to at least one of the wearable device or another of the multiple modular functional band links".

Each module would be linked to the next via a conductive material that would maintain a complete electrical circuit through the watch band. Another potential option could be a module that accepts a SIM card, allowing the watch to send and receive mobile communications without having to be tethered to an iPhone as in the case of the Apple Watch and Apple Watch 2.

The patent, spotted by Apple Insider, was filed in February 2015 but was only granted to Apple on 24 January of this year. This means it is unlikely to appear in the Apple Watch 3 in time for its predicted 2017 release window, although it may still be a tantalising glimpse of what is to come from Apple HQ in the not-too-distant future.