Comparison

Calcvier vs Error Note

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

Head to head
About

Calcvier

Transform your device's keyboard into a powerful calculator. Perform quick calculations directly within any app without switching screens or copying and pasting results.

Highlights
  • Calculator keyboard integration
  • Perform calculations anywhere
  • No app switching required
  • No copy-pasting results
  • Use in Notes, Mail, Safari, Messages
Features
Read full description

The Calcvier will turn your keyboard into Calculator! Add calculator keyboard to make fast calculations anywhere. No need to switch between apps or use some widget, no need to copy and paste results! To enable Calcvier on your device: 1) Open Settings app 2) Go to General > Keyboard > Keyboards 3) Tap Add New Keyboard... 4) Tap Calcvier You can use Calcvier keyboard in any app such Notes, Mail, Safari, Messages and other!

About

Error Note

Features
Read full description

Error Note — Study Smarter with Your Own Error Notebook Error Note is a simple but powerful tool designed to help students and exam-takers improve faster by reviewing past mistakes. Capture your wrong questions, organize them by subjects, and understand your weak points through clear statistics and structured review tools. Whether you are preparing for exams, learning new subjects, or trying to build better study habits, Error Note helps you focus on what truly matters: learning from your mistakes. Key Features 1. Add Mistakes Easily Record wrong questions using text, photos, or quick notes. Supports multiple subjects such as Mathematics, English, History, and more. 2. Organize by Subject and Topic Create your own subjects or chapters. Group mistakes logically and access them at any time. 3. Smart Review System Tag difficulty levels, set review reminders, and study using spaced repetition. Improve memory efficiently with guided practice. 4. Error Statistics and Weak Point Analysis See which subjects you struggle with the most. Track your progress over time and identify where to focus next. 5. Print Review Sheets Generate printable versions of selected questions, with or without answers. Ideal for exam preparation and offline study. Why Choose Error Note * Focus on mistakes that matter * Learn faster with targeted review * Build strong and consistent study habits * Track improvement clearly over time * Simple, fast, and distraction-free Error Note is a reliable companion for long-term learning and exam preparation. Study less, learn more, and make every mistake count.

Screenshots

Calcvier4 screens
Error Note4 screens

Verdict

The call

The clearest difference is price: Error Note at $0.99 against Calcvier's $2.99. Calcvier's advantage is iOS requirement (15.6 vs 17.0). On ads, in-app purchases 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

Calcvier costs $2.99 and Error Note $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Scorecard2 real differences · 8 level
Calcvier versus Error Note: the parameters behind the verdict, then further details
ParameterCalcvierError Note
Price$2.99$0.99 — better
Rating4.4 (143 ratings) — better—
Positive reviews81.2% of reviews—
Number of ratings143 — better—
Update frequencyEvery 8 months—
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.6 — better17.0
Further details — not scored
Size6 MB17 MB
Age rating4+4+
DeveloperSergei Shpygar建春 张

In-app purchases

None

Calcvier

No in-app purchases

None

Error Note

No in-app purchases

Questions

Is Calcvier free?
Calcvier costs $2.99, with no in-app purchases.
Is Error Note free?
Error Note costs $0.99, with no in-app purchases.
Do Calcvier or Error Note have ads?
Neither Calcvier nor Error Note shows ads.

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