App Overview

GrappleBell: Timer & Score icon

GrappleBell: Timer & Score

NariGroup LLC · Sports

GrappleBell is a simple, no-nonsense timer and scoreboard built for training and competition, especially Jiu-Jitsu and wrestling

$1.99

PRICE
$1.99
No in-app purchases
BUSINESS MODEL
Paid
No overall Grossing estimate available
RATING
★ 5.0
1 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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A product spec, phased build plan, differentiation notes, and screen references.

  • START_HERE
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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.
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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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App evidence

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

Screenshots

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App Store description

GrappleBell is a simple, no-nonsense timer and scoreboard built for training and competition, especially Jiu-Jitsu and wrestling. Set your rounds and go. TRAINING TIMER • Choose rounds, round length and rest, or load a Quick Start with one tap • Full-screen, color-coded display you can read from across the mat: orange to get ready, green rolling, amber near the end, red for rest • Landscape mode with a giant time and the controls on the side, perfect for mirroring to a TV or propping up across the room • A real ring-bell sound to start and end every round, a warning clapper before the round ends, and countdown beeps for the last seconds of rest • Pick your alert sound (Classic Ring Bell, Deep Bell, Air Horn, Buzzer, Chime), with a volume slider and test button • Pause, stop or skip at any time • Save your own Quick Starts: Positional Sparring, Open Mat Rolls, Comp Prep, Shark Tank, Drilling, or anything you make • Tap any time to dial it in with a scroll wheel COMPETITION TIMER FOR EVERY STYLE • Choose your rules: IBJJF, ADCC, JJWL, NAGA No-Gi, Fuji BJJ, UFC BJJ, Freestyle Wrestling, Folkstyle Wrestling, or a simple +1 / -1 scoreboard for local and regional tournaments • Each ruleset has its own score buttons, match lengths, periods and breaks: belt times for BJJ, USA Wrestling age-division periods, NAGA division times, ADCC qualifier and final formats • ADCC: scoreless first half, minus points for penalties, and overtime • Wrestling: takedowns, reversals, escapes, near falls and exposure, penalty points for your opponent, and technical superiority • Two-athlete scoreboard with editable names, plus advantages, penalties and wins by submission or pin • Optional IBJJF penalty rules: the 2nd penalty gives your opponent an advantage, the 3rd gives them 2 points, and the 4th is a disqualification • Corrections and undo at any time • Landscape layout puts both scores and the clock on screen at once Rules differ by event and year, so always check your event's rulebook. BUILT FOR THE GYM • Keeps the screen awake while a timer is running • Round alerts still fire if your phone locks or the app goes to the background • Louder sounds, with sound and vibration switches in Settings • Dark, high-contrast design • No account, no ads, no tracking

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Build scope

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Define the first version

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Set boundaries

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