Charlie Chang’s apps

Business Builder

Choose, validate, launch, operate, and grow a business.

The full arc: choosing a business, validating it, launching, running and growing it, with the app changing as the business moves between stages. It is aimed at somebody starting from nothing.

What a v1 does5 features
  • Choice, validation, launch and operations as sequential stages
  • The tools change as the business changes stage
  • Validation before build, enforced
  • Operating basics once there is something to operate
  • Growth work only once there are customers

The market

Adjacent marketBusiness planning and validation
$757Ma year at Coursera, from 197M registered learners

People pay reliably to learn how to run a business, and HoneyBook's 100,000 members show they pay to run one. Paying to validate an idea before starting is much less established. These are adjacent comparables rather than direct ones, and $29 a month should be read that way.

Where these numbers come from
CompanyEarnsReachSource
LivePlanConsumer-priced SaaSNot publishedPublished pricing
Coursera$757.5M revenue, FY2025197M registered learnersPublic filings, 2025
HoneyBook$1B+ booked100,000+ membersCompany-stated

Why this audience

This audience is at the very start and wants the whole arc, not one stage. The content walks people from nothing to something. A tool that changes as the business changes stage mirrors the journey they are already following.

Before it can launch

No licence, certification or data agreement stands between this and a launch — app-store review and an ordinary privacy policy aside.

What it earns

Drag me Every figure recalculates as you go.

Paying users1,000

0.05% of 2M followers · capped at 50,000

Price per month$29

Opens on the price this idea was costed at, $29.

1,000 paying — 0.05% of 2M followers — × $29 a month = $29,000 a month

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Revenue a month$01234567890123456789,012345678901234567890123456789
Over twelve months$012345678901234567890123456789,012345678901234567890123456789

Fifty thousand paying users is the ceiling every one of these pages is drawn against, not a forecast. It opens at a thousand, the bottom of the range, so the first figures you see are the modest ones. What the cap buys is comparability: the same range on every app, and the percentage of the audience it takes as the number that moves.

Is this the one for your audience?

We fund it, build it, and run it. You bring the audience and take a share of the revenue. Nothing to pay and nothing to build.

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