We spun up a HAT based on our Ultimate GPS, added a coin-cell holder for RTC usage, break-outs for all the Raspberry Pi's extra pins, and plenty of prototyping area for adding LEDs, sensors, and more.
Please note, this HAT takes over the Raspberry Pi's hardware UART to send/receive data to and from the GPS module. So, if you need to use the RX/TX pins with a console cable, you cannot also use this HAT. Instead, you'll have to use a composite or HDMI monitor and keyboard to log in, or use ssh to connect over the network to your Pi.
Comes as a fully assembled GPS + PCB and an additional 2x20 GPIO header. Some light soldering is required to attach the 2x20 GPIO header to the HAT but it's fast and easy for anyone with a soldering iron and solder. You can also swap the plain female header we have with a 'stacky' type that lets you plug in a hat or GPIO cable on top or a slim ultra-low-profile header.