App Overview

Adding Machine 10Key Universal icon

Adding Machine 10Key Universal

Richard Silverman · Finance

'Adding Machine 10Key Universal’ behaves like a true '10 Key' or 'adding machine' like those made by Monroe, Casio, Sharp and others

$3.99 · In-app purchases

PRICE
$3.99
In-app purchases
BUSINESS MODEL
Paid
No overall Grossing estimate available
RATING
4.7
134 ratings · Top 15%

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, 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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> SELECT BUILD PLATFORM:

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

// RORK SYSTEM PROMPT
Rork plan preview for Adding Machine 10Key Universal: map the core Finance 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

Add features like memory functions and scientific calculations.

Assumption to check: Limited functionality for advanced calculations or features.

Validate with people who use this workflow before building.

Hypothesis 2

Implement export functionality for calculations.

Assumption to check: No export or share option for history.

Validate with people who use this workflow before building.

Hypothesis 3

Allow users to customize themes and button layouts.

Assumption to check: No customization options for the interface.

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

'Adding Machine 10Key Universal’ behaves like a true '10 Key' or 'adding machine' like those made by Monroe, Casio, Sharp and others. Press asterisk (*) for a total, operator entry is reversed, and calculate percentages by multiplying and adding to a stream of numbers. SEE THE 1ST FAQ BELOW. This universal version works with both iPhone and iPad. The iPad version features a full sized (1:1) keypad with TypeTone, a unique audio aid to help guide your finger back to the center of a key. The total (*) key (iPad or iPhone) can be on either the left or right side (Sharp or Canon style). Also. Review & edit numbers, add or delete lines. Save & retrieve paper tape files. Export paper tape files to iBooks©, Dropbox©, or your favorite printing utility (see the FAQs). ==== Recent Press ===== Has been featured in iTunes "What's Hot" in the Finance Category. Strategic Finance (Tools of the Trade): "If you're looking for a professional desk calculator that can give you full 10-key accounting functions with a tape you can name and save, edit, e-mail, or print, check out Interlocken's 10 Key for iPad." ================= Specifications: ================= . Behaves the same as a '10 Key' adding machine. . Export a PDF file to iBooks©, DropBox©, Email, and print with your favorite printing utility. . Use Apple AirPrint© to print directly. . TypeTone - a major innovation to aid accurate key entry using audio feedback (iPad version). . Full size (1:1) keyboard (iPad version). . Select from a menu of keypad sounds. . 400 lines of paper tape history. . 3 display formats: fixed, fix+, float . Save paper tapes to disk for later use. . Correct numbers, add comments, add/delete lines . Two keypads offer the 'total' key on the left or right (Sharp or Canon style) . Comprehensive set of help screens. . 3 Orientations: Landscape Left/Right + Portrait (iPad version) ================ FAQ's Q1. What is the difference between 'Adding Machine 10Key Univ', and 'Accountant Calc' in the App. Store.? A1. Both calculators are single-column adding machines or calculators with full-size (1:1) keypads and are optimized for the iPad User Interface. '10 Key' behaves the same as a 10 Key Adding Machine with reversed operator entry while ‘Accountant Calc’ supports free chaining of +, -, x, /, %, √, 1/x. It is easier to use if you are not familiar with how a '10-key' works. Q2. Can I touch-type? A2. The iPad version comes as close to touch-typing as a touch-screen can be. With ‘TypeTone’, a key will guide your finger back to the center of a key with an audio tone. Q3. How can I edit an incorrect number or add & delete lines from the paper tape? A3. Touch any line of the paper tape for edit mode. Touch the side controls: Add Line, Delete Line. You can also edit numbers, split Add/Sub or Mul/Div groups. Press Done to return to Calculator mode. Q4. Tell me about Email, Printing, and Exporting a Paper Tape. A4. Email includes a pdf attachment. Print requires an AirPrint capable printer. Open-In will cause a menu of 3rd party Apps to appear. Once exported, print directly to a network reachable printer (even if it is NOT AirPrint capable). ============================ TERMS AND CONDITIONS Your use of this application is governed by Interlocken Technology's Terms of Use (http://s354819480.onlinehome.us/InterlockenPrivacyPolicy/Interlocken%20Technology%20Privacy%20Policy.pdf) and Privacy Policy (http://s354819480.onlinehome.us/InterlockenPrivacyPolicy/InterlockenTechnologyTermsOfUse.pdf)

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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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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.