A phone sealed in a SeaTouch 6 Pro is still a phone. The whole touchscreen stays live to 60 meters, you drive it with a bare finger through the flexible membrane, and there is no companion app to install and no special camera mode to configure. That changes the question divers ask. It stops being whether the camera works, and becomes which of the other things already on your phone are worth opening at 12 meters.
Three answers come up repeatedly: identifying a fish while you are still looking at it, capturing a small subject in three dimensions, and typing something down before you forget it. Here is what to try, what to realistically expect, and where each one runs out of road.
Set the Phone Up Before You Seal It
The SeaTouch 6 Pro is a button-free housing. Once the phone is inside, its volume, power and side buttons are sealed in and cannot be pressed, and every input you make travels from your fingertip through the membrane to the phone's own screen. That single input path is what makes all of these apps possible, and it is also the thing you can accidentally break before you get wet.
The way to break it is a native "underwater mode." Several manufacturers implement theirs by switching the touchscreen off and mapping the shutter onto the volume keys, which is a sensible design for a bare phone at the beach and a disaster inside a full-touchscreen housing, because a housing shell has no mechanical buttons of its own for you to press instead. Leave those modes off. The one verified exception is Samsung's Ocean Mode, which lives inside the Expert RAW app under Labs and stays touchscreen-driven, so it works normally through the membrane. If you want a physical trigger for gloved or cold hands, that comes from the Bluetooth Underwater External Shutter, which mounts in either of two positions on this housing for a left- or right-hand grip.
A few more minutes of preparation makes the difference between using an app and fighting one:
- Download offline data before you leave the dock. Species databases, map tiles and app models often need a connection the first time.
- Put the phone in airplane mode with notifications silenced, then raise the screen brightness. A call arriving mid-capture will push your app off screen.
- Move the apps you plan to use into one home-screen row, so switching takes one swipe rather than a search.
- Keep the screen protector on if your phone has one. The sixth-generation membrane is designed to work with it, which was not always true on earlier housings.
One quiet upgrade matters more here than in pure photography. The touch window on the SeaTouch 6 Pro covers more of the screen than the previous generation, so large phones regain the native swipe-up gesture to return to the home screen instead of relying on AssistiveTouch. App switching underwater used to be the clumsiest part of this whole idea, and it is now close to how the phone behaves in your hand on land.
Fish ID: Treat Every Answer as a Starting Point
Two approaches are worth trying. Seek by iNaturalist runs its identification on the device and gives you a suggestion without an account and without uploading anything, while iNaturalist proper records an observation that goes to community review and needs a connection to do it. The iNaturalist help article comparing the two is the clearest explanation of which one does what. The second option is Linne Lens, the app DIVEVOLK names in its own SeaTouch 6 Pro material for identifying fish on the spot.
What to expect: a suggestion, usually to family or genus, that is best when the subject is distinctive, reasonably still, well lit, and filling a decent part of the frame. What to expect less of: a fish moving away at three meters in green water, a juvenile that looks nothing like the adult, or a cryptic species where the diagnostic feature is a fin ray count. Water also removes red before it reaches the sensor, which strips out the color cue an ID model leans on, so the included snorkeling red filter is doing double duty here. Our explainer on why colors fade underwater covers why a corrected frame identifies better than an uncorrected one.
Treat every result as something to check afterwards. Photograph the animal, note the depth and habitat, and confirm against a regional guidebook or with the dive guide back on the boat. That habit also gives your log real content, which the guide to building a useful dive-photo log goes into.
The limit worth naming plainly: an app on your screen does not replace the briefing. Your guide is the one who tells you which species at that site are protected, which ones are venomous, and how close the local rules let you get. Identify from a distance and stay there. NOAA Fisheries' marine life viewing guidelines set out the basics: do not approach, touch, feed or chase an animal, and keep off the coral. Nothing an ID app tells you is worth a closer approach.
3D Capture: Run It as an Experiment
Photogrammetry underwater is a real technique with a real scientific history. NOAA Ocean Exploration's overview of photogrammetry describes the workflow: many overlapping images from many angles, processed into a point cloud, then a mesh, then a texture. Consumer apps like Polycam and Scaniverse do that same processing on a phone. A DIVEVOLK user has already built 3D models of underwater scenes this way, and that 3D mapping story is the honest version of what it takes.
Some practical notes before you try it. Use the photo-based capture mode rather than the LiDAR mode, since the phone's depth sensor does not read reliably through water. Pick shallow, clear, bright water and a subject that will not move: a coral head, a piece of wreck structure, a bommie, an anchor. Orbit it slowly at a steady distance with generous overlap between frames, keep the sun out of the frame, and give the subject the middle of the screen. A slow deliberate circuit produces a better model than a fast one with twice the frames.
Expect failures, and expect them often. Surge moves you and the subject during the pass. Suspended particles confuse the solve. Fish swimming through the scene leave holes. Water absorbs light with distance so the far side of a subject comes back darker than the near side, which is where a video light from dive lights earns its place. And the processing is the most demanding thing you can ask a phone to do on a dive, so watch the battery.
Treat what comes back as a picture rather than a measurement. A model built on a recreational dive with a phone is a lovely thing to show people and a poor basis for saying a wreck has moved 40 centimeters since last year. If you want that, the scale references and control points belong in the water with you, and that is a survey, not a snorkel.
Typed Notes: Useful, and Strictly Secondary
The simplest of the three is also the most immediately useful. Open a notes app, type the depth, the species, the setting you changed, the name of the site, whatever you would otherwise try to hold in your head until you surface. We wrote a whole guide on typing underwater with a phone housing, and the short version is that it works better than most divers assume once the keyboard is where your thumb expects it.
Typing also lets you show a buddy a sentence that no hand signal covers, which is genuinely handy when you want to point out something specific or agree on a plan change. What it does not do is send anything. Cellular and Wi-Fi do not travel through water, so a message you type at depth sits in the outbox until you surface. The DIVEVOLK SeaLink transmitter is the exception, carrying a phone's signal from as deep as 30 meters to a surface unit, and that is a purpose-built piece of hardware rather than something your phone does on its own.
The boundary here is not negotiable. Standard hand signals remain the primary way divers communicate, and they are the only thing fast and unambiguous enough for an ascent, a gas check, or a problem. DAN's guidance on clarifying hand signals before diving makes the case for agreeing them in the predive briefing, and no typed note replaces that. Screens also cost attention, and attention underwater is finite. Add one new on-screen task at a time, on a dive where you have spare capacity, and drop it the moment anything else needs you.
How to Try Any of This Without Ruining a Dive
The same progression works for all three. Run the app on land with the phone in your hand until you know where every control is. Run it again with the phone sealed in the housing, still dry, so you learn what the membrane feels like under a small button. Then take it into a pool or a shallow entry. Only then bring it on a real dive, and bring one new app at a time.
Nothing on this list should be debugged at depth. If an app misbehaves at 15 meters, close it, take the photograph the ordinary way, and sort it out on the surface. That is also the general rule in our phone housing tips and techniques guide.
If you shoot on Android and want a camera app built for the water rather than adapted to it, our deep dive into the UWACAM underwater camera app covers the manual controls and color handling that a stock camera app leaves out. And if you are still deciding which housing puts your phone in the water, start at underwater phone housings.
