Luna Review: A moon pendant that taps you when it’s time

I set reminders on my phone all the time, and I still miss about half of them. Not because they don’t go off. They do. It’s that they go off in the same place as everything else, so a note about calling the plumber ends up sitting under two group chats and a shipping update, and I clear the lot without reading it.

That was on my mind when I came across Luna on Kickstarter. It’s a small steel pendant shaped like a crescent moon, and its main trick is tapping you on the chest when something you asked to remember comes due. I was curious, and a little skeptical, so I spent some time going through the campaign, the specs and the founders’ updates to see what it is and isn’t.

The company behind it is Moonshot, a three-person startup from San Francisco that’s part of Y Combinator. Luna is 27 mm wide, which puts it close to the size of a quarter.

How it works

The idea is pretty simple. You wear Luna on a chain, and it connects to your phone over Bluetooth. When you want to remember something, you say it out loud. Two mics in the pendant pick up your voice and pass it to Samantha, Moonshot’s app on your phone.

Later, when the reminder is due, a small motor in the pendant taps you. The stone face lights up. If you have earbuds in, you hear what the reminder is about. If not, your phone says it.

That’s more or less it. There’s no screen on Luna, and I think that’s the part that makes it interesting. When my phone buzzes, I don’t know if it’s important until I look, and looking is where my attention goes sideways. With Luna, the tap only ever means one thing. Whether that’s enough to change a habit is up to the person wearing it, but the logic makes sense to me.

Moonshot says the tap is meant to be felt only by the wearer. I can see that working at a dinner table or in a meeting, where checking your phone every so often gets noticed.

What it looks like

This is where Luna doesn’t look like most AI wearables. A lot of them are clips or pins that look like tech, and you can tell from across the room. Luna looks like a necklace.

The case is 316L stainless steel, polished on the sides and brushed on the back, and the design target is about 6 mm thick. The face is an opal-white stone that lets light through, so the glow comes out soft instead of sharp. It hangs on a 50 cm steel chain with a 5 cm extender.

Whether you’d wear a moon every day is personal. I like how it looks. Some people won’t, and that’s fine. It’s still a piece of jewelry first, so taste matters more here than it does with, say, earbuds.

The first 300 backers can have a personal goal engraved on the back, which Moonshot calls your “moonshot.” It’s a sweet idea, if a bit on the sentimental side.

About the microphones

I wouldn’t wear anything with microphones near my face without knowing how they’re handled, so I looked at this part closely.

Luna has no camera. You turn the mics off by tapping the pendant twice (a motion sensor picks it up), and twice again to turn them back on. The app can do it too. Moonshot has said it’s still finishing this double-tap feature on its prototypes.

When the mics are on, your voice goes over an encrypted Bluetooth connection to the app and then to Samantha’s servers. The company says it doesn’t sell anyone’s data. Transcripts, and the notes Samantha makes from them, are kept until you delete your account.

The mics are TDK T5838 parts, each set in its own sealed chamber. That’s meant to help with fabric noise, which seems like the obvious problem for something worn on a chain.

The app, and what it costs

Luna doesn’t run any AI on its own. Its firmware covers the tap, the light and the mute, and that’s it. The rest happens in Samantha, which uses models from OpenAI and Anthropic, with ElevenLabs handling speech and voice.

So you need your phone nearby, with an internet connection, for Luna to do anything. I don’t see that as a dealbreaker, but it’s worth being clear about. Luna works more like an accessory for an app than a standalone device.

The app is also a separate cost. No Kickstarter reward includes it. It’s free for six months. After that the core features stay free, and Premium is $20 a month or $200 a year. Moonshot is upfront about this on the campaign page, which I appreciate, but if you were planning on Premium, add that to the price of the pendant before you decide.

Battery and charging

There’s a 35 mAh battery inside. On the current prototypes, Moonshot says it lasts a little over two days, depending on how long the mics stay on. The company is aiming for three.

Two days means charging every other night. That’s similar to a lot of smartwatches, so most people who already wear one won’t find it a big change.

It charges in a small box with a night sky printed inside the lid. You set the pendant on three metal contacts and plug the box in over USB-C. Kickstarter backers also get a braided cable.

On water, Moonshot is designing Luna for splash and sweat resistance. Rain and workouts, then, but I’d take it off before a shower or a swim.

Who’s making it

Ojas Kandhare, the CEO, was studying to become a heart surgeon before he left premed to start companies. He and his co-founders, Tario and Dylan, say they went through 26 failed ventures before one worked. After that they built an app called OpenTrade that reached 225,000 weekly users, then shut it down because none of them used it.

They say Luna came from wanting to make something they’d use themselves. That’s easy to say. Still, the backstory is unusually candid for a crowdfunding page.

This is their first hardware product, and they don’t hide that. According to the campaign, the first steel cases and stone faces were made in October, the circuit board is working, and the app can already make prototype electronics tap and glow. FCC certification and Bluetooth qualification are planned for January 2027. Shipping is estimated for February 2027, with the engraved units first.

The risks section is more detailed than most I read. It lists things like Bluetooth range through steel, how the mics do under clothes, the final light patterns and battery life. The team also promises a build update with photos every Friday until shipping.

Pricing

Moonshot plans to sell Luna for $599 once it’s in stores. On Kickstarter, the engraved version is $389 for people who paid a $1 reservation, and $399 for the first 300 backers otherwise. A regular Luna without engraving is $449, and two cost $700. There’s also an eight-pack for $2,999 and a $2,500 tier that includes dinner with the founders in San Francisco.

Each one comes with the charging box, the chain and a two-year warranty. Shipping and taxes are added after the campaign.

At the time of writing, the campaign has raised $52,513 from 129 backers. The goal was $10,000. It runs until December 10, 2026.

Who it’s for

I think Luna makes the most sense for people who want to use their phone less but still have a lot of small things to keep track of. Parents come to mind. So do people who spend most of their day in meetings or on their feet.

It’s not trying to be a fitness tracker, a camera or a full voice assistant, so if you want one of those, this isn’t it.

For me, the appeal is how little it does. It taps, it glows, it tells you what you asked to be told, and then it leaves you alone. There’s the app subscription to think about, and it’s a first product from a young team. But if you’ve ever cleared a reminder without reading it, the idea behind Luna will probably make sense to you.