While there may be more than a dozen multi-device wireless chargers technically available now, most do not charge both smart watches and smartphones – and most of the companies who make them could not actually provide units for review since they're bring offered through crowdfunding projects.

As a result, we're limiting this review to multi-device chargers from three stalwart companies and a start-up that promptly shipped over a review unit.

[ Further reading: Wireless charging explained: What is it and how does it work? ]

Samsung's Wireless Charger Duo

Samsung