Carl's Workout

Custom workout builder and tracker. Build programs, log sets and reps, and track progress over time.

Type: live. Platform: ios. Year: 2024.

Every workout app I tried wanted me to follow their programmes. I just wanted to log my own. Carl's Workout is a personal tool built around one idea: you know your training better than an algorithm does. Build your own programmes, log exactly what you lifted, and see progress over time without the noise.

Why I built this

Every workout app I tried wanted me to follow their programmes. I just wanted to log my own. Carl's Workout is a personal tool built around one idea: you know your training better than an algorithm does. Build your own programmes, log exactly what you lifted, and see progress over time without the noise.

Stack

  • React Native
  • Expo
  • Replit
  • Claude
  • AsyncStorage

Learnings

  • Building for one user (yourself) is liberating - no feature compromise, no stakeholder negotiation.
  • AsyncStorage is fine for personal apps at this scale. I didn't need a backend.
  • The hardest design problem was the logging flow. It needed to be fast enough to use mid-set.

Every workout app I tried wanted me to follow their programmes. I just wanted to log my own. Carl's Workout is a personal tool built around one idea: you.

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