watchOS 4.3 release notes

watchOS 4.3 reinstated the ability to browse and control music on your paired iPhone, enabled new features like portrait Nightstand mode, squashed several bugs and fixed more than a dozen vulnerabilities.

iOS 11.3 release notes

In addition to headline-grabbing features like performance throttling, iOS 11.3 packs in a bunch of little things, under-the-hood tweaks and fixes that make this another recommended software update for your iPhone, iPad and iPod touch.