Your phone is the viewfinder.

What it does

Tether the camera and the phone becomes a big, bright viewfinder you can actually work from — mounted on the hot shoe, clamped to a tripod, or in your hand.

About the coach

This is the part people ask about, so here it is plainly.

Aperi never touches your photograph. It doesn't generate images, retouch them, or edit anything. It reads the frame you're composing and the settings you're using, and tells you what it sees — the way an instructor looking over your shoulder would. The shot stays entirely yours.

Two real sessions

Both of these happened. The coaching quoted is what the app actually replied to the first frame in each pair — written before the second photograph existed, and checkable against the EXIF.

Shifen Waterfall — moving water

The coach

The main issue is your shutter speed of 1/50. It is in a no-mans-land for moving water, making the falls look messy rather than intentional.

To get that classic, silky water, switch to Manual mode, keep ISO 100, and close down to f/16 to force a longer shutter speed, aiming for 1/2 or slower. You will need a tripod.

You either freeze water completely at 1/1000 or paint with it at 1 second. Let us slow it down.

The advice named 1/2 of a second; the next frame was shot at exactly that. Both on the same 18mm prime and ISO 100 — three stops of aperture bought the slower shutter. The framing changed too: APS-C crop mode was switched on and the tripod moved a step closer, so the water is not the only difference you are looking at.

Night street, Taiwan — where the colour lives

The coach

Your brightest highlights, like those blue and white neon signs, are completely blown out.

In night street photography, colour lives in the highlights. Because you are in A mode at exposure compensation 0, the camera is trying to make the dark asphalt neutral, which overexposes the signs.

Dial your exposure compensation down to -1.3 EV. This will protect those rich neon colours and clean up your shadows.

Let the darkness frame your light.

The advice asked for about a stop and a third less exposure; the frames measure 0.99 EV darker. The camera also moved to Manual, which stopped auto-ISO wandering between 800 and 3200 from one frame to the next, and stopping down to f/2.8 put more of the street in focus. It is meant to be darker — that is where the neon gets its colour back.

Connecting

Which cameras

Being straight with you, because nothing is more annoying than installing an app that can't see your camera.

The AI coach needs an API key from Google, Anthropic or OpenAI — you bring your own, it stays on your phone, and your photos go straight to the provider you chose. Everything else — live view, focus, exposure, the card browser — works without one.

Beta testers with a Sony body other than the A7 V are especially welcome — that's how the list above gets longer.