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DarkRoast Labs / Custom apps

The tools you rely on
should work harder.

We turn the spreadsheets and workflows you already know into custom HTML apps that are easier to use, share, and grow.

Fill out the form to get started
The problem

Your spreadsheet
has outgrown itself.

×Fragile formulas no one wants to touch

×Important work trapped on one person's laptop

×No easy way to use the tool from a phone

×Shared via email, so finding the most current version feels impossible

Imagine having a custom tool that makes running your business easier, not harder.

Before and after comparison of a spreadsheet transformed into a custom real estate analysis app
The solution

A custom app
built on your logic.

We preserve the useful logic inside your existing spreadsheet, then give it a clean interface your whole team can actually use.

  • Replace fragile formulas with a reliable interface
  • Make the app useable on any device
  • Share a polished tool with your team or customers
Selected work

Custom tools,
beautifully made.

Real Estate Analyzer app preview
Custom app

Real Estate Analyzer

A multifamily underwriting tool that turns deal inputs into clear scenarios, cash flow, and return metrics.

Cash Flow Ledger app preview
Custom app

Cash Flow Ledger

A focused cash flow forecast that makes recurring bills, balances, and decisions easier to see.

Quick Deal Calculator app preview
Custom app

Quick Deal Calculator

A mobile-first deal calculator for quick underwriting when the next opportunity cannot wait.

How it works

A straightforward way
to move forward.

01

Get started

Fill out the contact form and tell us what your spreadsheet does, along with any changes you would like in an app version. We will follow up and ask you to send the spreadsheet so we can review it.

02

Mockup and quote

We review how the spreadsheet works, then create a non-calculating mockup with the additions, colors, and styling you requested. We will send it to you with a clear quote.

03

We build your app

Once you approve the mockup and quote, we build the working app to match the approved design.

04

Receive your custom app

You will usually receive your new app within 2–3 days, along with a short guide explaining how to use it and how the calculations behind each field work.

Fill out the form to get started
Pricing

Simple pricing.
Clear expectations.

One Sheet

$149

For one simple list or tracker

Multi-Tab

$299

For connected sheets and tabs

Workbook

$449

For complex, multi-feature tools

Start a project

Tell us what
you're thinking.

No jargon, no hard sell. Fill out the form and we'll reply with a sensible next step.