Bubbletrail Dive Log

Bubbletrail is a free, open-source dive log for recording and organising
your scuba dives. It connects directly to dive computers over Bluetooth,
imports logs from Subsurface and other programs, and displays dive profiles
including depth, temperature, tank pressure, and calculated deco. Whether
you're a recreational diver or into technical diving with multiple gas
mixes, Bubbletrail keeps your dive history in one place.

The app aims for a modern, intuitive interface and surfaces best-practice
metrics like surface gradient factors (SurfGF) to help you understand your
dives better.