Subsurface Alternative? Read This Before You Switch
Short version, up front: Subsurface is free, open-source, actively maintained (latest release within the last few months), supports over 200 dive computers across 28 brands, and runs natively on Windows, Mac, and Linux. That's more platform coverage than almost every paid competitor, mine included. If you plan trimix dives with real decompression obligations, its planning tools are more capable than most consumer logbook apps will ever be. If someone told you Subsurface is dead or bad, they're wrong.
What follows is a straight comparison: three things Subsurface does better than Currents, three things it does worse, and who should switch versus who shouldn't.
Where Subsurface Wins
Cost. Free, forever, no subscription, no paywalled export, no "Pro" tier. Desktop, mobile, cloud sync, all of it. That's better than every paid app on the market, Currents included.
Dive computer support. Over 200 models across 28 brands via libdivecomputer, the same open-source library most of the ecosystem runs on. Diving something obscure or older, Subsurface is more likely to support it than a smaller consumer app's device list.
Platform coverage. Native desktop apps on Windows, Mac, and Linux at once is rare. Most competitors, Currents included, are iOS-first or iOS-only, with a web view standing in for desktop. Work across all three operating systems and Subsurface is one of the few apps that doesn't make you compromise.
Where It Falls Short
The interface assumes you already know what you're looking for. Subsurface's UI reflects its roots as a tool built by and for technical divers: dense tables, a planning-first layout. That's a feature for its core audience and a wall for someone who wants to glance at "how was my last dive" without parsing a decompression table.
Mobile is a reduced version of desktop. Subsurface-mobile logs dives and syncs Bluetooth LE computers, but importing UDDF or FIT files still requires the desktop app. If your workflow is entirely phone-based, log the dive on the boat, never touch a laptop, you'll hit that wall.
Bluetooth sync fails in specific, documented ways. One poster on ScubaBoard running a Shearwater Perdix 2 on Windows 11 described it exactly: "When I go to sync my dives with SubSurface, my dive computer doesn't show, it throws an error. It doesn't see my dive computer." Their fix, deleting the Bluetooth device in Windows and re-pairing it, sometimes repeatedly, before the laptop would see the computer again. On the Subsurface Google Group, the same pattern shows up against a Shearwater Petrel ("Error opening the device Petrel") and a Scubapro Aladin Matrix H, where a firmware update broke Bluetooth import until a workaround was found. It's not one bad review, it's the same category of failure recurring across different computers and different users.
There's also no social or community layer, by design. Subsurface is a logbook and dive planner, not a place to see what your buddies logged. That's not a shortcoming, it's just not what the app is trying to be.
Who Should Stay, Who Should Look Elsewhere
Stay on Subsurface if you're a technical diver, if you split time across Windows, Mac, and Linux, or if free-forever matters more to you than interface polish. It's a strong tool for that person.
Look elsewhere if the interface, the mobile limitations, or the lack of a community layer are the actual friction. That's the specific gap apps like Currents fill: Bluetooth sync from 15+ dive computer brands, a modern iOS interface, buddies and site reviews alongside the logbook, and UDDF import so your Subsurface history comes with you. Currents doesn't cover 200 computers, doesn't run on Linux, and isn't free forever. That's the trade, not "Subsurface bad, Currents good."
Export your logbook to UDDF before you decide anything either way. It keeps the option open without committing you to it.
