Comparison

Twin vs OPQRcoder

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

Head to head
About

Twin

This app combines two calculators into one, allowing for side-by-side or stacked calculations. Easily copy and paste results between calculators or to other apps. It displays formulas for clarity and handles basic arithmetic operations.

Highlights
  • Two calculators in one
  • Side-by-side and stacked display
  • One-touch copy/paste between calculators
  • Copy results to iPhone memory
  • Formula display
  • 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 free version with ads. Please try it first. https://apps.apple.com/jp/app/t-calc-lite/id1630026837?l=jp 【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. Note The free version can be downloaded from https://apps.apple.com/jp/app/t-calc-lite/id1630026837?l=en

About

OPQRcoder

Features
Read full description

Standard QR codes contain unused "padding" bytes after the encoded data. OPQR writes your image into those bytes — invisible to scanners, visible to eyes. Select an image or take a photo and generate code with any text.

Screenshots

Twin4 screens
OPQRcoder3 screens

Verdict

The call

The clearest difference is price: OPQRcoder at Free against Twin's $0.99. Twin's advantage is in-app purchases (none vs 1) and update cadence (every 2 weeks vs every 16 months). On ads and device support 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

OPQRcoder is free to download; Twin costs $0.99 up front. OPQRcoder sells 1 one-off in-app purchase. Twin asks for nothing beyond the download.

UpkeepUpdate frequency

Twin ships an update every 2 weeks, OPQRcoder every 16 months. The most recent releases landed on September 26, 2026 and September 25, 2026 respectively.

Scorecard4 real differences · 6 level
Twin versus OPQRcoder: the parameters behind the verdict, then further details
ParameterTwinOPQRcoder
Price$0.99Free — better
Rating5.0 (8 ratings) — better—
Positive reviews76.0% of reviews—
Number of ratings8 — better—
Update frequencyEvery 2 weeks — betterEvery 16 months
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaid—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS13.0 — better15.1
Further details — not scored
Size1 MB37 MB
Age rating4+9+
DeveloperHiroyuki UedaTakaho Endo

In-app purchases

None

Twin

No in-app purchases

1 purchases

OPQRcoder

One-time1
  • OPQRcoder Pro$1.99

Questions

Is Twin free?
Twin costs $0.99, with no in-app purchases.
Is OPQRcoder free?
OPQRcoder is free to download, with in-app purchases available.
Do Twin or OPQRcoder have ads?
Neither Twin nor OPQRcoder shows ads.
Which is updated more often, Twin or OPQRcoder?
Twin ships an update every 2 weeks, and OPQRcoder every 16 months. Most recently, Twin was updated on September 26, 2026 and OPQRcoder on September 25, 2026.

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