Charlie Chang’s apps

FounderOS

Entrepreneur operating system for priorities, calendar, deep work, AI, learning, routines, and relationships.

One system for the parts of a founder's week that usually live in six tools: priorities, calendar, deep work, learning, routines and the people to stay in touch with. It is opinionated about what a week should contain.

What a v1 does5 features
  • Priorities that drive the calendar rather than sitting beside it
  • Deep work blocks protected and measured
  • Routines and habits tracked without a separate app
  • Relationships surfaced when they have gone quiet
  • A weekly review across all of it in one page

The market

Proven marketTask and daily planning
50M usersat Todoist, of whom roughly 300,000 pay

That is about 0.6% conversion at the most successful independent task manager there is. Motion went from $2M to $50M in under two years charging $19 to $34 a month, and Sunsama charges $16 to $20. At $19 a month this sits at the lower end.

Where these numbers come from
CompanyEarnsReachSource
Todoist$26.5M a year50M+ users · ~300k paying customersIndependent estimate
Motion$2M to $50M ARR in under two yearsNot publishedIndependent estimate
Sunsama$16–20/moNot publishedPublished pricing, 2026

Why this audience

This audience treats their own week as something to be engineered, which is a specific and unusual disposition. They have watched enough systems content to want one system rather than six apps. That appetite is what makes an operating system for a week sellable at all.

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$19

Opens on the price this idea was costed at, $19.

1,000 paying — 0.05% of 2M followers — × $19 a month = $19,000 a month

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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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