The BCM4774 is second-generation GNSS location hub with Galileo support, described by Broadcom.
The GPSTest Database shows the BCM4774 in various Samsung phones and tablets:
The BCM47748 was announced on 17 Sep 2015 in GPSWorld.
It is a GNSS chip for the Internet of Things (IoT) and wearable devices , simplifying integration of GNSS into low-cost products.
The BCM47748 may have been used in the Apple Watch Series 3 and Series 4, but that is purely speculation.
The BCM4774 was announced on 2 Sep 2014 in PR Newswire and on 7 Jan 2015 in GPSWorld, adding support for Galileo.
There is a basic functional analysis on Tech Insights and websites such as ST Mobile Parts have a list of phones that use the BCM4774.
The BCM4774 appears in some Samsung phones and watches, including:
It also appears in Huawei products, including: