Comparison

T vs Instructions

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

T

This app offers a dual calculator interface, allowing side-by-side or stacked calculations. Easily transfer results between calculators with a single touch for complex computations. It displays formulas for clarity and allows copying results to your device's memory.

Highlights
  • Two calculators in one
  • Copy and paste results between calculators
  • Input results from one calculator to another
  • Formula display
  • Copy results to device memory
  • Supports basic arithmetic operations
Features
Read full description

A simple and easy-to-use calculator app that combines two calculators into one. Calculators are displayed side by side when the screen is horizontal, and vertically when the screen is vertical. In addition to being able to perform separate calculations with each calculator, calculation results can be also copy and paste with one touch, so you can perform other calculations during calculations, making it even more convenient to use than you might imagine. There is also a paid version without ads. Please try it first. https://apps.apple.com/jp/app/twin-calc/id1619292082 【feature】 1. Calculation results can be copy and paste between two calculators with one touch. 2. The result calculated can be input from one calculator to the other with one touch. ・When press the "→" key, the calculation result of the left calculator is entered at the end of the formula on the right calculator. ・When press the "←" key, the calculation result of the right calculator is entered at the end of the formula on the left calculator. 3. add, subtract, multiply and divide is performed. Do multiplication and division first, then add and subtract. 4. Display the formula The entered formula is displayed under the result, so you can easily check the operations. 5. Calculation results can be copied to iPhone’s memory Calculation results can be pasted into other apps as text , so transcription errors will not occur. Example of use When you find a product for 988 yen for 3 pieces and a product for 1245 yen for 4 pieces while shopping, you can easily calculate "Which is cheaper?" And “How cheaper?"with this calculator. 1) Use the left and right calculators to find the unit price of the product (unit price = product price/number). 2) Tap the "- key" and "arrow key" on either the left or right calculator to calculate the unit price difference. Limitations ・Answer can be calculated up to 9 digits, minimum 0.000000001.

About

Instructions

Features
Read full description

Key Features - Register, save, search, and share PDFs - Import PDFs shared from other apps - Organize PDFs into categories - No account required - Supports web page registration - Simple and intuitive interface Keep manuals and technical documents at your fingertips—offline! This app lets you register and manage PDF manuals and reference materials so you can search and read them anytime, even without an internet connection. You can also bookmark websites for quick online access when needed. Perfect for professionals and tech users who want to organize manuals, guides, and documentation in one place—and stay productive, even when offline.

Screenshots

T4 screens
Instructions4 screens

Verdict

The call

The clearest difference is in-app purchases: T at none against Instructions's 1. T also leads on ads (none vs shown). On price, update cadence, device support and iOS requirement there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Instructions sells 1 one-off in-app purchase. T asks for nothing beyond the download.

UpkeepUpdate frequency

T ships an update weekly, Instructions fortnightly. The most recent releases landed on October 30, 2026 and October 25, 2026 respectively.

Scorecard2 real differences · 8 level
T versus Instructions: the parameters behind the verdict, then further details
ParameterTInstructions
PriceFreeFree
Rating5.0 (2 ratings) — better—
Positive reviews42.9% of reviews—
Number of ratings2 — better—
Update frequencyWeekly — betterFortnightly
AdsNo — betterYes
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.015.0
Further details — not scored
Size4 MB15 MB
Age rating4+17+
DeveloperHiroyuki UedaKazuhisa Kobayashi

In-app purchases

None

T

No in-app purchases

1 purchases

Instructions

One-time1
  • Remove Ads$4.99

Questions

Is T free?
T is free to download, with no in-app purchases.
Is Instructions free?
Instructions is free to download, with in-app purchases available.
Do T or Instructions have ads?
Instructions shows ads; T does not.
Which is updated more often, T or Instructions?
T ships an update weekly, and Instructions fortnightly. Most recently, T was updated on October 30, 2026 and Instructions on October 25, 2026.

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