CalendarDuo vs Basic Calculator.
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
CalendarDuo
Easily manage and view holidays from two different countries simultaneously. This utility app offers instant switching between calendars, a dual-view display, and helpful tools like a world clock and currency exchange.
- Switch between two world calendars instantly
- Duo-view with holidays from two countries
- Daylight Saving Time dates
- Currency exchange rate
- World clock
- Add notes
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** This app does not access your Contact List or Calendar. ** CalendarDuo allows users to switch between two calendars at their fingertips! CalendarDuo is the best tool for: - Frequent flyer between two countries/regions - Organizing events with family members or relatives overseas - Scheduling meetings and tasks with colleagues overseas - Planning trips to another country/region - ANYONE who needs a simple calendar! Top features - Switching between TWO world calendars INSTANTLY - Duo-view displaying ONE calendar with holidays of TWO countries/regions - User interface with multiple language selection - Daylight Saving Time (DST) dates - Currency exchange rate (for currencies available in Europe Central Bank) - World clock - Adding notes CalendarDuo is the simplest calendar you’ll ever need! NEW! 2026 holidays are available now! - public holidays - bank holidays - statutory holidays - regional holidays - provincial holidays - special days NEW! 2022 World Calendars (more are coming!): - Australia - Canada - China (PRC) - France - Germany - Hong Kong - India (Maharashtra, New Delhi) - Indonesia - Italy - Japan - Macau - Malaysia - Philippines - Portugal - Singapore - South Korea - Taiwan - Thailand - United Kingdom - United States - Vatican City Holiday information is gathered from government official releases. Source details can be found on each Holiday List.
Basic Calculator.
A straightforward and user-friendly calculator app designed for quick calculations. It features a display log, a backspace key for corrections, and supports both decimal points and commas.
- Display log for calculations
- Backspace key for corrections
- Decimal point and comma support
- Designed for quick calculations
- User-friendly interface
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Introducing the ultimate basic calculator app - simple, easy-to-use, and packed with features to help you get the job done. Our calculator is designed with you in mind, whether you're a student, a professional, or just need to do some quick calculations. We've also included a a display log for your calculation and result, a backspace key for correcting or changing numbers, and support for decimal point or decimal comma Download our calculator app today and see for yourself why it's the must-have tool for anyone who needs to do quick calculations on the go.
Screenshots
Verdict
The clearest difference is in-app purchases: CalendarDuo at none against Basic Calculator.'s 1. Basic Calculator.'s advantage is update cadence (every 2 weeks vs every 4 months) and iOS requirement (13.0 vs 15.1). On price, 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
Both are free to download. Basic Calculator. sells 1 one-off in-app purchase. CalendarDuo asks for nothing beyond the download.
CalendarDuo ships an update every 4 months, Basic Calculator. every 2 weeks. The most recent releases landed on October 15, 2026 and October 17, 2026 respectively.
| Parameter | CalendarDuo | Basic Calculator. |
|---|---|---|
| Price | Free | Free |
| Rating | — | 4.7 (147 ratings) — better |
| Positive reviews | 50.0% of reviews | — |
| Number of ratings | — | 147 — better |
| Update frequency | Every 4 months | Every 2 weeks — better |
| Ads | Yes | Yes |
| In-app purchases | No — better | Yes |
| Monetization | Ad-supported — better | Free with in-app purchases |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 15.1 | 13.0 — better |
| Further details — not scored | ||
| Size | 41 MB | 69 MB |
| Age rating | 4+ | 4+ |
| Developer | Chun Lam | Edison Largo |
Customer experience
CalendarDuo
Basic Calculator.
In-app purchases
CalendarDuo
No in-app purchases
Basic Calculator.
- Remove Ads$3.99
Questions
Is CalendarDuo free?
Is Basic Calculator. free?
Do CalendarDuo or Basic Calculator. have ads?
Which is updated more often, CalendarDuo or Basic Calculator.?
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