Charlie Chang’s apps

Switch Your Environment

Recommend work environments based on the task.

Different work wants different surroundings, and most people use one desk for all of it. This suggests where to do the task in front of them, based on what has actually worked for them before.

What a v1 does5 features
  • Suggestions matched to the type of task
  • Learned from where this person has actually worked well
  • Nearby options - cafe, library, park - with practicalities
  • Noise, light and seating noted per place
  • A record of what produced good work, and where

The market

Adjacent marketFocus and blocking
3M usersat Freedom, which charges from $3.33 a month

Opal charges $19.99 a month or $99 a year for the same job. Neither publishes revenue, so the prices are the evidence. At $4 a month this sits inside a range the category has already established.

Where these numbers come from
CompanyEarnsReachSource
Freedom$3.33/mo annual · $199 lifetime3M+ users and teamsPublished pricing
Opal$19.99/mo or $99/yrNot publishedPublished pricing, 2026
ForestNot publishedTop-5 most-installed focus appCategory ranking, 2026

Why this audience

These viewers work from anywhere and have noticed that where they work changes what they get done. That observation is already theirs. Matching the place to the task turns a suspicion into a routine.

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$4

Opens on the price this idea was costed at, $4.

1,000 paying — 0.05% of 2M followers — × $4 a month = $4,000 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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