CalcBox vs Error Note
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
CalcBox
This app combines numerous essential calculation tools into a single, user-friendly interface. It handles everything from basic arithmetic and unit conversions to financial planning, health tracking, and academic performance. Simplify your daily tasks with this comprehensive utility.
- Basic and scientific calculations
- Extensive unit and currency conversion
- Financial calculators (loan, deposit, tip, discount)
- Health and fitness trackers (BMI, ovulation)
- Time and date calculations (D-Day, world clock)
- Academic tools (GPA calculator)
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CalcBox makes life more convenient with its user-friendly design and smart calculation functions. It efficiently handles various real-life calculations, integrating multiple tools into one app, and features a simple, intuitive interface that anyone can use. Download CalcBox now and simplify your life! ▷ Calculator Perform basic arithmetic and simple scientific calculations quickly. Equations and results can be saved for future use. ▷ Unit Converter Convert units like area, length, temperature, weight, volume, data, time, speed, pressure, force, energy, fuel efficiency, and more, making it versatile for various needs. ▷ D-Day Calculator Calculate days leading up to important dates or see how many days have passed since an anniversary. ▷ World Clock Converter Check the time in cities around the world or calculate the time across different time zones. ▷ Currency Calculator Quickly convert exchange rates for international travel or transactions, with offline use supported via saved rates. ▷ BMI Calculator Enter your height and weight to calculate your BMI and BMR, and visualize results through saved graphs. ▷ Unit Price Calculator Compare prices by calculating the unit price of multiple products. Save and modify results as needed. ▷ Tip Calculator Conveniently calculate tips for meals or services, including per-person splits. ▷ Percentage Calculator Useful for financial transactions, accurately calculating discounts, and taxes. ▷ Discount Calculator Easily find the final price after discounts, including VAT calculations. ▷ Loan Calculator Check financial status by calculating loan repayments and interest. ▷ Deposit and Savings Calculator Calculate future savings by applying deposit amounts and interest rates, including simple and compound interest calculations. ▷ VAT Calculator Accurately calculate the final price including VAT. ▷ Fuel Efficiency Calculator Determine your car's fuel efficiency based on mileage and fuel consumption. ▷ Fuel Price Calculator Calculate your car’s fuel cost using mileage and gas prices. ▷ Ovulation Date Calculator Predict ovulation and fertile windows, supporting family planning and cycle tracking with health notes. ▷ GPA Calculator Track academic performance by calculating GPA, aiding in academic planning. ▷ Age Calculator Calculate your age by entering your birth date, with the option to save and edit results. ▷ Pace Calculator Determine running pace by entering distance and time, including treadmill speed conversion. [Disclaimer] Realbyte Inc. disclaims any responsibility for the accuracy, appropriateness, or reliability of the data provided by the CalcBox app. The company is not liable for errors, omissions, or any damages arising from defects, delays, interruptions, or reliance on the app's information. Subscription pricing and terms: CalcBox offers a $0.99/month auto-renewing monthly subscription and a $9.99/year auto-renewing annual subscription, which removes ads and allows users to choose additional app design themes while maintaining an active subscription. Payment will be charged to the credit card connected to your iTunes Account when you confirm the initial subscription purchase. Subscriptions automatically renew unless auto-renew is turned off at least 24-hours before the end of the current subscription period. Your account will be charged for renewal within 24-hours prior to the end of the current period, and the cost of the renewal will be identified. You may manage your subscription and auto-renewal may be turned off by going to your Account Settings after the purchase. Read more about our terms and conditions here: https://www.apple.com/legal/internet-services/itunes/dev/stdeula Privacy Policy: https://calcbox.realbyteapps.com/privacy.html
Error Note
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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
Verdict
The clearest difference is price: CalcBox at Free against Error Note's $0.99. Error Note's advantage is in-app purchases (none vs 2) and ads (none vs shown). On 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
CalcBox is free to download; Error Note costs $0.99 up front. CalcBox sells 2 in-app purchases, starting at $0.99 per month. Error Note asks for nothing beyond the download.
| Parameter | CalcBox | Error Note |
|---|---|---|
| Price | Free — better | $0.99 |
| Rating | 4.8 (362 ratings) — better | — |
| Positive reviews | 92.5% of reviews | — |
| Number of ratings | 362 — better | — |
| Update frequency | Every 3 weeks | — |
| Ads | Yes | No — better |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | — |
| Devices | iPhone, iPad | iPhone, iPad |
| Requires iOS | 16.6 — better | 17.0 |
| Further details — not scored | ||
| Size | 72 MB | 17 MB |
| Age rating | 4+ | 4+ |
| Developer | Realbyte Inc. | 建春 张 |
Bugs and requests
CalcBox
Reported bugs
3 issues- Ads cannot be closed with X button
- Excessive ads appearing after initial use period
- Deceptive ad behavior after one week of use
Requested features
6 requests- One-time payment option to remove ads permanently
- Premium ad-free version (like Money Manager app)
- Set as default calculator option
- Deposit/savings calculator with day-level precision
- Bitcoin/cryptocurrency support
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- Account checking integration with calculation features
Error Note
Not enough reviews yet to summarise bugs or requests.
In-app purchases
CalcBox
- 1 Month Subscription3 Days trial$0.991 Month
- 1 Year Subscription3 Days trial$9.991 Year
Error Note
No in-app purchases









