Casio decides it's about time the simple digital watch got a little smarter

Casio has added Bluetooth and step tracking to a £55 digital watch without turning it into a smartwatch or sacrificing replaceable-battery convenience.

The snappily named F-B100W pairs with Casio's smartphone app to record activity, adjust settings, and keep its clock accurate.

Despite the additional electronics, Casio claims approximately two years of operation from a replaceable CR2016 battery.

It is very much not a smartwatch.

There is no touchscreen, app store, or stream of notifications – just a conventional digital watch with a step counter and a little Bluetooth connectivity.

That combination has nevertheless attracted attention on Hacker News and Reddit.

We admit it: this ape-descended life form is so astoundingly primitive that he still thinks digital watches are a pretty neat idea.

Douglas Adams first mocked humans' fondness for digital watches when the original Hitchhiker's Guide to the Galaxy was broadcast in 1978 – nearly half a century ago.

The Casio F-91W is only a decade younger.

This strangely ubiquitous watch, once labeled a supposed "sign of al-Qaida," is widely regarded as the classic quartz digital watch and has been described as the bestselling watch of all time.

One reason is that it's only £20 ($30) new.

Another is that if you bought one of the first batch, it's probably only on its third or fourth battery by now: they are rated for seven years, but often last longer.

The F-91W is very simple and very cheap.

Its main rival for all-time bestselling watch is the reverse: the Apple Watch has also shifted about 300 million units.