Doorbook.
Start here

Set the building up once

Doorbook asks for three things before it can bill anything: how you want to be paid, what you charge per unit, and what each meter reads today. Ten minutes now and the app does the arithmetic for the rest of the building's life.

5 min read Updated 2026-08-13

There is no account to create and no sign-up. Open the app and it starts asking questions, because everything it needs lives on your phone.

  1. 1Payment

    Choose how tenants pay you

    Doorbook builds a payment QR into every bill. Pick the standard your country uses — PromptPay in Thailand, VietQR in Vietnam, KHQR in Cambodia — or upload a photograph of your own bank or wallet QR if you are anywhere else. You can change this later in Settings → Payment.

  2. 2Rates

    Set your default rates

    Enter what you charge per unit of electricity and per unit of water, plus a monthly internet charge if you levy one. These become the starting values for every new room, so set them to whatever most of your rooms pay. A room that is different can override them individually.

  3. 3Currency

    Check the currency

    Doorbook picks a currency from your app language — baht for Thai, dong for Vietnamese, yen for Japanese, and so on. If that is wrong for you, change it in Settings; fourteen currencies are available and the choice is independent of the language you read the app in.

  4. 4First room

    Add a room

    Give it a number, the rent, and — this is the important part — the current reading on its electricity and water meters. That opening figure is the line Doorbook measures the first month's usage from.

Why the opening reading matters more than anything else

A utility meter is a counter. It does not report what a room used this month; it reports everything the meter has ever counted. Doorbook works out consumption by subtracting last month's figure from this month's — so the first figure you type is the baseline for the first bill.

Walk the building with the app open and type each meter's face value as you stand in front of it. It is the single most valuable ten minutes you will spend in Doorbook.

The home screen after setup: every room, what it owes, and what has come in.
The home screen after setup: every room, what it owes, and what has come in.

What you do not have to do

  • No account, no email, no password. Nothing is registered anywhere.
  • No tenant app. Tenants never install anything — they receive a bill and a QR code.
  • No connection. The whole app works offline, which matters because meter cupboards are where signal goes to die.
  • No card details. Doorbook is free for your first 18 rooms.

Read next