Share what you rarely use with the neighbours you choose.

Your building is full of things people use a few times a year. CoNabo helps neighbours borrow them, co-own them, and buy new only when nobody nearby has one.

Clickable prototype. Next: a pilot with friends. Progress

A pressure washer — Example. Selling three shares gives the owner up to 1,800 kr back.

Borrow free, give back. Own what you use a lot.

Join with a code from your building's board or an invite link, or start your own community.

1Borrow

Free, with a thanks that fits

Borrow a neighbour's thing for free. The app suggests a thanks, so the owner never has to ask.

2Own a share

Using it often is fine. Leaning on a neighbour isn't.

Take a share: you get your own days, repairs are split, and the owner gets money back.

Move out: you sell it back.

3Co-buy

Buying it anyway? Buy it together.

Say "I want one too", anonymously. When enough neighbours want one, someone starts a co-buy and everyone pays their part.

Why would an owner share a nice thing?Free, but give back

Owners won't put a good thing out if everyone takes it for nothing, and an owner who asks for something looks stingy, so in practice nobody asks. CoNabo is neither a free-stuff app nor a rental shop:

The app suggests the thanks. No prices. Ideas that fit the thing: the next soap refill for a pressure washer, new bits for a drill, a coffee or a cake.
Heavy users own their part. After two uses in a year the app suggests taking a share, framed as fairness, not savings.
Money back, or help. Selling three 25% shares in a 2,400 kr washer brings up to 1,800 kr back, and it stays at your door. A neighbour can also pay for a share with upkeep, repairs or storage space.
No credits, no score. Only you see your give and take, plus a nudge at the right moment: "The neighbour who lent you the drill is looking for a ladder."

The owner always decides who borrows and when.

What does owning a share mean?A receipt, not a contract

Who owns it: Every thing has one registered owner, whose home insurance covers it.
What you get: Your own days on the calendar.
How you pay: A share is priced from what the thing is worth today. You pay the owner directly, for example by MobilePay, or with upkeep instead of money.
The record: A receipt everyone in the group can see: who paid what, and when.
If it breaks: A condition photo at every handover. Repairs are split by ownership; if it was your fault, you can take on more.
If you move: You sell your share back. It's optional and reversible; borrowing for free is always there.

How does a co-buy work?From "I want one too" to a shared thing

The app checks the building first: if a neighbour already has one, you borrow or take a share instead.
Neighbours who want one tap "I want one too", anonymously. Nobody has to organise anything yet.
Anyone can start the co-buy and write the plan and house rules in their own words. The app adds plain notes as they write: what's vague, what's missing, what's easy to forget.
Others join. The group meets, one person buys it and shares the receipt, and everyone pays their part.
The thing gets a passport: registered owner, co-owners, receipt and rules.

Co-buys are only for things that last. Used-up things like groceries are split elsewhere.

How do you join?Three ways in

I have a code: Your building's board puts a note on the notice board with a code.
I have an invite link: A neighbour or friend sends you a link.
Start a community: Your building, a club, friends or roommates. You get an invite link to share.

Then three short steps: pick your door (buildings only), read how it works here, and add a few things you could share.

What holds it together

You choose who you share with

Not the whole building. You share with the neighbours you pick.

Private until you meet

Neighbours you haven't met see a track record, not your name or door.

A receipt, not a contract

Every thing has one registered owner. The app keeps a clear record of who paid what.

Fewer, better things

Sharing what already exists means less gets made.

We never hold your money

You pay each other, for example by MobilePay, and the other side taps when it has arrived.

Meet in person

The first handover is face to face, and we encourage meeting before any money changes hands.

Small decisions that make it workEach came from feedback or research

Asking for something looks stingy: The app suggests the thanks.
Heavy users ride on one purchase: After two uses: own your part.
Credits rank people: Private give and take, no score.
A list of names feels like surveillance: Private until you meet.
A map of every door helps burglars: A thing is placed at a door only once you know the owner.
Hard rules sound like a landlord: The owner's note, in their own words.
Rules that sounded clear start fights: Plain notes as you write: "'Be careful' is vague."
Stars don't tell people apart: A track record: handovers, claims, reply time.
Nobody wants to organise a co-buy: "I want one too" first, anonymously.

What we won't doTen things CoNabo is deliberately not

Rent things out for money: No prices on borrowing, no earnings from lending. Thanks are suggested, never charged.
Hold or move money: No wallet, no escrow, no card details. People pay each other and tick "I've paid" / "Got it".
Write contracts or insure things: One registered owner whose home insurance covers the thing, and a receipt everyone can see.
Rate people: No stars, no scores, no public ranking. Only what someone has actually done.
Be a marketplace for strangers: Things are shared inside your building, community or circle.
Deliver or store things: No couriers, lockers or depots. Handovers happen in person, at a door.
Be a chat app or a feed: Short requests with polite templates; no endless feed, no group chats.
Show ads: None. The one product suggestion is a labelled durable pick inside a co-buy.
Split rent, bills or groceries: Bill-splitting apps already do that well.
Co-buy things that get used up: CoNabo records who owns what over years; a can of tuna has nothing to share later.

The market wants every flat to own a drill. Your building needs one.

Much of what's sold today is built to be replaced. Sharing means fewer sales, longer use, and things that get fixed.

58%of Danes already share, swap or borrow things. 48% say we should share more.Bolius/YouGov, 2021

755 kgof household waste per Dane in 2023. The EU average is 511 kg.Eurostat

29.5%of Copenhagen homes are andelsboliger: co-op flats, each run by a board of residents.Københavns Kommune, 2021

More of the evidenceNeighbours, care, scale and policy

17%: of Danes know all their neighbours' names; 39% know none or only a few. Bolius/YouGov, 2023
Owned things get looked after: People look after what they own and neglect what they only access, so we build on co-owning. Bardhi & Eckhardt, 2012
97,529 co-op homes: of 330,492 in Copenhagen. Every andelsforening has a volunteer board of neighbours. Københavns Kommune, 2021
60,400+ items: shared from 22 sites by Library of Things in London. Hackney's sites averaged 47 loans a week each. Library of Things, 2024/25
Right to repair: The EU directive had to be national law by 31 July 2026: manufacturers must repair more of what they sell. Directive (EU) 2024/1799

The gap in Copenhagen's waste strategySharing is named, but not covered

Copenhagen's waste strategy for 2025–2030 says people should be helped to share, repair and pass on things. Its initiatives are reuse stations, swap events, school teaching and a fund for local projects. None of them helps neighbours use the same thing together.

Københavns Kommune, Ressource- og Affaldsstrategi 2030, theme 4

What we don't claimBeing honest about the numbers

We don't put a CO2 number on CoNabo. Money saved by sharing can be spent on other things: a UK food-sharing study found this cancels 59–94% of the CO2 saved. What we can say is that sharing what exists, and co-owning instead of buying alone, means fewer things get made.

Meshulam et al., Journal of Industrial Ecology, 2023

Questions people ask

Who's legally responsible?

We're a platform for easier social contracts: one registered owner per thing, and a clear record of who paid what. Home insurance usually covers your things while they're temporarily away from home, and the borrower's liability insurance covers damage they cause, but terms differ between insurers. We'll get an insurer's written answer before a pilot.

What if it breaks?

A condition photo at every handover. Repairs are split by ownership, and if it was your fault you can offer to cover more.

What about a difficult neighbour?

You only share with the people you choose. You can report or block a neighbour, and report a thing.

Isn't buying a share a big step?

It's optional and reversible: you sell it back if you move, and borrowing for free is always there. Nobody has studied buying into a neighbour's thing yet, so we'll measure it in the pilot.

What if everyone wants it on Saturday?

People skip a shared thing if they fear it won't be free when they need it, so the app plans for peaks from the start:

Fair turns. Peak days, like summer Saturdays, rotate so nobody always wins.
Real availability. Before you join, you see how often it was free.
Short slots and a waitlist. Half a day for a drill, a weekend for a tent.
Too busy? Add one. If it's fully booked too often, the app suggests co-buying a second.

Lamberton & Rose, Journal of Marketing, 2012; Akbar, Journal of Business Research, 2019

Will anyone start?

Every building needs one person to get the first groups going. A free app alone isn't enough: Peerby, a Dutch lending app, grew to 30+ cities and still had to restructure in 2018. That's why we start with one building, a champion and real offers.

Where we are

Four phases. Each starts only once the one before it works.

Now: a clickable prototype with made-up data, and a backlog of 63 work items, each tied to the phase that first needs it. Nothing is launched yet.

Pilot · Friends

Test the idea with friends: share things, take a share, receipts, the calendar, co-buying.

20 work items

MVP

Pilot · Building

One building we set up ourselves: the board's code, privacy, handovers in person, notifications.

+15 work items

Launch

v1

Grows on its own: start a community, invite links, connect by code, plus the polish.

+23 work items

Later

v2

New kinds of sharing: hobby circles, a hand from a neighbour, roommates, the board chipping in.

+5 work items

What's in each phaseAll 63 work items, in plain words

Pilot · Friends 20

What's in the building
Item passport
The owner's note
Borrow request
Owner reply
Take a share
Check and confirm
Receipt and MobilePay
Co-owner calendar
Your door
Share something
Pay with upkeep
What the owner gets back
Co-buy proposal
Wanted: I want one too
Join a co-buy
Co-buy something new
Co-buy savings
Ask first: does a neighbour have one?
Run the co-buy

Pilot · Building (MVP) +15

Board invite and code
Pick your door
Quick inventory
Notifications
Today
Search the building
Knock card, meet first
Condition photo
QR handover
Return
Neighbour track record
Private until you meet
Report and block
Delete your account
How it works here

v1 +23

Start a community
Three ways in
Invite links
Where things are now
Floor by floor
Borrow, co-own, co-buy
Fair-share nudge
Handover log
Message templates
Saturday turns
Waitlist
Repair split
Leave it better, say thanks
Neighbours you know
Connect by code or in person
Meet before money
Leave a share
Ways to give back
Private give and take
House rules in your words
Notes as you write rules
How we share here
Why we do this

v2 +5

The board chips in
Hobby circles
Ask for a hand
Roommates: who paid what
Durable pick

How it could growOne building first, then outward

One building: First things co-owned. Sharing happens every week. Groups run without us.
The courtyard: Several associations around one gård share through the app.
A neighbourhood: Boards in one neighbourhood adopt it.
Copenhagen: The app pays for itself.
Other cities: Aarhus and Odense, then Nordic cities with co-op housing like Oslo and Stockholm.

It spreads two ways: through housing boards and community managers, which brings trust, and neighbour to neighbour, through a stairwell poster with a real offer, invite links, courtyard parties and hobby groups. Either way density counts: 20 users in one building beat 200 spread across the city.

How it's fundedOur own company, backed by grants and funds

CoNabo is planned as our own company, funded by grants and funds for the pilots. It isn't run by or sold to the kommune.

Lokaludvalg puljer: Copenhagen district funds for local community projects. Good for a pilot's events and materials.
KK Inspirationskvarterer: The fund in the city's 2030 waste strategy for local projects.
Realdania: Foundation for the built environment and local communities, with open calls for grassroots projects.
Innovationsfonden: Innofounder and, later, Innobooster.