All Side Hustle Ideas
Software and apps

Gym app built through constant testing

A gym app whose founder treats product development like a science experiment, using A/B tests and feature validation to decide what to build.

At a glance
Estimated by a classifier that read the source. The bar shows how sure it was.
Category
Software and apps
97% sure
x
Earns from
Subscriptions
91% sure
x
Startup cost (estimate)
$1k to $10kLow confidence
47% sure
x
Time it takes (estimate)
Part-timeLow confidence
50% sure
x
Where
Online
97% sure
x
Coding
Needs coding
98% sure
x
Source
Starter StoryMauro, with Pat Walls. “How I Built This $160K/Month Gym App”, September 9, 2026
In their words, not verified by us$160,000 last month

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