The Belkin "3-in-1 Magnetic Foldable Wireless Charger with Qi2 15W" (or similar models) is primarily optimised for Apple devices, but it also supports Qi-compatible devices in general.

- Samsung S24 and other Samsung smartphones: As these chargers use Qi2 technology, they are generally compatible with Qi-compatible Samsung smartphones. So you can charge your Samsung smartphone wirelessly, but possibly not at the same speed as Apple devices, as the maximum charging power for non-Apple devices may vary.

- Samsung Galaxy Watch: These chargers are specifically designed for Apple Watch models and have no specific support for Samsung Galaxy Watch. It is unlikely that they will be able to charge the Samsung Galaxy Watch.

- Samsung Buds: Similar to the Apple Watch, the chargers are mainly designed for AirPods and other Apple earbuds. There is no specific support for Samsung Buds and it is therefore questionable whether they can charge them.

To summarise: The Charger is likely compatible with Qi-compatible Samsung smartphones, but is not specifically designed for Samsung Galaxy Watch or Samsung Buds.