App Overview

Chronograph Log icon

Chronograph Log

On-Core Software LLC · Sports

Chronograph Log was developed to record your bullet velocities, from your Chronograph, onto your iOS device

$3.99 · In-app purchases

PRICE
$3.99
In-app purchases
BUSINESS MODEL
Paid
No overall Grossing estimate available
RATING
4.0
3 ratings · Top 30%

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 included17 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 Chronograph Log: map the core Sports 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

Allow users to customize activity types and add icons.

Assumption to check: Limited customization options for activities.

Validate with people who use this workflow before building.

Hypothesis 2

Implement better filtering and sorting options.

Assumption to check: Difficulties in viewing long-term statistics.

Validate with people who use this workflow before building.

Hypothesis 3

Simplify the interface and focus on key actions.

Assumption to check: User interface can be cluttered.

Validate with people who use this workflow before building.

Hypothesis 4

Ensure robust cloud syncing features.

Assumption to check: Inconsistent data syncing issues.

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

Chronograph Log was developed to record your bullet velocities, from your Chronograph, onto your iOS device. No more writing everything down on a pieces of paper to be lost in your range bag. When your friends ask about the loads you are using, you can pull out Chronograph Log and give them accurate info instead of guessing. Send them an email or message on the spot. Share your favorite loads via eMail, Facebook and more. Chronograph Log was primarily developed for USPSA IPSC and IDPA, where Minor and Major Power Factors are very important. It will color code those entries based on their velocities. Note that the Power Factors can be ignored if you are tracking rifle loads or don’t care about Power Factors. Note: This application is not a chronograph. You will need to enter readings from your chronograph into the Chronograph Log app. • Define: Bullets, Guns and Powder in the database. • Record velocities for each round from your chronograph. • Automatically calculate Average, Min and Max velocities. • Color coding to show each velocity’s Power Factor. • Export full tables to Mail. • Export favorite loads to Messages, Mail, Twitter or Facebook. • Backup / Restore to Dropbox. • Bluetooth integration with Competition Electronics "ProChrono Digital" using their "Digital Link" module.

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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.

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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.