App Overview

1-RM icon

1-RM

Bodybuilding.com · Health & Fitness

Whether you're a competitive lifter or just want to improve your strength and fitness, your one-rep max (1RM) is an essential tool

$1.99 · In-app purchases

PRICE
$1.99
In-app purchases
BUSINESS MODEL
Paid
No overall Grossing estimate available
RATING
4.8
1,056 ratings · Top 5%

Evidence scope: No current overall US chart position is available. Category-chart positions shown in discovery are a separate scope. Revenue is a directional model estimate, not verified earnings.

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Build Kit

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A product spec, screen plans, and build steps for your coding agent.

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What's included16 files

A product spec, phased build plan, differentiation notes, and screen references.

  • START_HERE
  • AGENTS
  • EVIDENCE
  • SPEC
  • BUILD_PLAN
  • DIFFERENTIATION
  • skills/
  • screens/
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Illustrative example: an invoice app for independent contractors. Your kit is tailored to the app you choose; this is not its generated content.

Feature spec

Goal: Send a clear invoice after finishing a job.

  • Add a client, line items, a due date, and payment instructions.
  • Preview the total before exporting a PDF.
  • Keep an editable draft if export fails.

Screen plan

Invoice editor: Client at the top, editable line items in the middle, total and preview action at the bottom.

States: Empty draft, validation errors beside each field, exporting, and a retry action that preserves the draft.

Differentiate and validate

Hypothesis: Contractors need faster repeat invoices more than more templates.

First experiment: Test duplicating a previous job with five contractors. Watch where they hesitate before expanding the feature set.

The full kit adds a phased build plan, evidence notes, tool prompts, and implementation guidance. It is a plan for your coding agent, not a finished app.

Usage: Mechanics are fair game; never reuse the original name, branding, assets, or verbatim copy.

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Quick prompt

> SELECT BUILD PLATFORM:

Good fit for mobile-first iOS and Android prototypes with managed app scaffolding.

// RORK SYSTEM PROMPT
Rork plan preview for 1-RM: map the core Health & Fitness workflow, choose the smallest differentiated feature set, define the data and monetization boundaries, then prototype the riskiest user journey first.
            

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Opportunities

AI-GENERATED OPPORTUNITY HYPOTHESES

These are generated suggestions, not verified review quotations. Check current App Store reviews and speak with users before treating a possible gap as a requirement.

Hypothesis 1

Include a wider array of exercises and custom options.

Assumption to check: Limited exercise variety compared to competitors.

Validate with people who use this workflow before building.

Hypothesis 2

Simplify pricing and provide clear value for premium features.

Assumption to check: Subscription model can be confusing.

Validate with people who use this workflow before building.

Hypothesis 3

Incorporate community challenges and sharing options.

Assumption to check: Lack of social features.

Validate with people who use this workflow before building.

Hypothesis 4

Add support for HealthKit/Google Fit for better sync.

Assumption to check: No integration with fitness trackers.

Validate with people who use this workflow before building.

App evidence

Original App Store material. Ratings and screenshots describe the existing app, not proof of demand for your version.

App Store description

Whether you're a competitive lifter or just want to improve your strength and fitness, your one-rep max (1RM) is an essential tool. Calculate your max safely and easily, and then track it over time, on any lift with our easy-to-use calculator! In the simplest terms, your 1RM is the amount of weight you can lift for one rep on any given lift. In general, it’s good to know your max for key lifts like the squat, bench press, and deadlift, but your 1RM is critical even if you never plan to train that heavy. Many lifting programs are designed with a percent of your rep max in mind, and may call for something like using 65% of your 1RM for a given exercise. When you see that, you have to either test for your 1RM or estimate it. Testing your 1RM can be pretty intense, and it requires a high degree of caution to avoid injury. Fortunately, you can estimate your 1RM without testing it! Exercise scientists have devised a formula that's fairly accurate for most people, which is what powers this calculator. Our calculator makes it easy to calculate and track your 1RM and multiple percentages of it for every lift in the book! Features: · Calculate your 1RM and percentages · Choose from a variety of lifts (deadlift, bench press, squat, etc.), or add your own · Track and chart your 1RM history for each type of lift · Add notes each time you calculate your 1RM · Improve your weight training with articles by Bodybuilding.com experts · Choose imperial or metric system · Incredibly easy to use!

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Screenshots

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Build scope

Plan a focused first version with your coding agent. These are planning assumptions, not a delivery guarantee.

Define the first version

Choose one audience and one core workflow. Use the kit to agree on its screens, data, and acceptance criteria before building.

Set boundaries

Decide which secondary features, integrations, and platform support can wait. Your version does not need to reproduce everything in the original.

Check the hard parts

Validate external services, specialist technology, data access, and ongoing costs for your chosen scope.

SUGGESTED BUILD STACK
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BUILD KIT DIFFICULTY
Starter

From the Build Kit assessment.

A reliable timeline needs an agreed scope and a technical check. Ask your agent to estimate the phases in BUILD_PLAN.md after that review.