Caleido (formerly Event Book) vs Calendars
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Caleido (formerly Event Book)
This app offers a streamlined approach to managing your schedule and to-dos. It features a customizable interface with integrated map and weather information for efficient planning. Syncs with existing calendars and provides multiple view options for events and tasks.
- Calendar and task management
- Customizable interface
- Map and weather integration
- Syncs with existing calendars
- Multiple view options (day, week, month, list, location, task)
- Event and task management
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Featured by Apple, TechCrunch, and more! Caleido is a free, simple, and beautifully re-imagined calendar and task app. With usability and simplicity in mind, Caleido’s uniquely customizable interface along with map and weather integration helps you easily manage your life. With Caleido you can: ∙ Instantly sync with all your existing iOS calendars (iCloud, Gmail, Yahoo, Exchange, Hotmail, AOL, and more). ∙ Manage events, tasks, and frequent locations with day, timeline, week, month, list, location and task views. Full map, contact, location, and weather integration keep you one step ahead. ∙ Customize your experience with iPhone 7 (Silver, Space Gray, Gold), iPhone SE (Blue, Green, Red), and seasonal themes!
Calendars
This app helps you manage your schedule, tasks, and habits across all your Apple devices. It offers features for planning your day, building routines, and boosting productivity with seamless syncing and integration with other calendar services.
- Daily, weekly, monthly calendar views
- Event creation and reminders
- Integrated agenda planner
- To-do list and task management
- Natural language event/task input
- Habit tracking and routine building
- Cross-device syncing
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Calendars by Readdle is the all-in-one calendar, task manager, daily planner, and habit tracker — seamlessly working across all your Apple devices: Mac, iPhone, iPad, and Apple Watch. Plan your day, build better habits, boost productivity, and stay organized with powerful features and smooth sync between all your devices. What you can do with Calendars: • View and manage your calendar with daily, weekly, and monthly views • Create events, set reminders, and never miss important dates • Use the built-in agenda planner to focus on what matters most • Organize your to-do list and manage your tasks with ease • Quickly add events or to-do items using natural language • Build routines and track your habits to stay consistent • Take a guided productivity course to improve time management and focus • Sync across devices with Google Calendar, iCloud, and more • Customize your planner calendar with color coding and widgets • Join Zoom, Google Meet, or GoToMeeting directly from your calendar • Stay in control of your time, wherever you are Whether you're planning a busy workday, building new habits, or working on personal growth, Calendars brings everything together to help you own your time — across all your Apple devices. Privacy Policy: https://readdle.com/calendars/legal/privacy Terms of Service: https://readdle.com/calendars/legal/terms Have questions, comments, or issues? Don’t hesitate to reach out to us at http://readdle.com/contact
Screenshots
Verdict
The clearest difference is rating: Calendars at 4.7 against Caleido (formerly Event Book)'s 3.8. Calendars also leads on update cadence (weekly vs every 2 months) and ratings volume (123K vs 5). Caleido (formerly Event Book)'s advantage is in-app purchases (none vs 10) and review sentiment (74% vs 56%). On price and ads 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. Calendars sells 10 in-app purchases, starting at $3.99 per month. Caleido (formerly Event Book) asks for nothing beyond the download.
Calendars holds the better App Store score, 4.7 against 3.8. That said, the two scores are not equally well evidenced: Calendars has 123K ratings behind it against 5, so its average is the more settled of the two. Written reviews complicate that: 74% of Caleido (formerly Event Book)'s written reviews are positive against 56% of Calendars's, so the app with the better star average is not the one people write more warmly about.
Caleido (formerly Event Book) ships an update every 2 months, Calendars weekly. The most recent releases landed on November 6, 2026 and November 13, 2026 respectively.
| Parameter | Caleido (formerly Event Book) | Calendars |
|---|---|---|
| Price | Free | Free |
| Rating | 3.8 (5 ratings) | 4.7 (123K ratings) — better |
| Positive reviews | 73.5% of reviews — better | 56.0% of reviews |
| Number of ratings | 5 | 123K — better |
| Update frequency | Every 2 months | Weekly — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Free — better | Free with in-app purchases |
| Best chart rank | — | #110 — better |
| Devices | iPhone, iPod | iPhone, iPad, Mac, Apple Watch — better |
| Requires iOS | 7.0 — better | 18.2 |
| Further details — not scored | ||
| Size | 13 MB | 414 MB |
| Age rating | 17+ | 4+ |
| Developer | Abhinay Ashutosh | Readdle Technologies Limited |
Customer experience
Caleido (formerly Event Book)
Calendars
User reviews
Caleido (formerly Event Book)
From 5 App Store ratingsWhat we love
- 👍 Clean, intuitive, and minimalist interface
- 📅 Multiple view options (day, week, month)
- ⚡ Fast and responsive performance
- 🎨 Beautiful design with customizable themes
- 🔗 Seamless integration with iOS calendar
Room to improve
- 🐛 Frequent crashes and stability issues
- 🐛 Weather widget not working properly
- 🐛 Location/map integration failures
- 🐛 Alarm/notification system unreliable
- ❌ No push notifications for reminders
Calendars
From 123K App Store ratingsWhat we love
- 🌟 Excellent calendar app
- 👍 Easy to use and organize
- 🎨 Helpful color-coding
- 📆 Seamless integration with other calendars
- 🗓️ Detailed monthly/weekly views
Room to improve
- 🐛 Occasional glitches and data loss
- 💰 Concerns over subscription model
- 🕰️ Cumbersome date/time selection process
- 🔍 Limited location search functionality
- 🔄 Sync issues between devices
Bugs and requests
Caleido (formerly Event Book)
Reported bugs
17 issues- App crashes when setting alarms or editing events
- Weather widget fails to load or display
- Location services cause repeated permission requests
- Month view displays events one day before actual date
- Week view shows incorrect day labels (Sunday appears twice)
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- Events disappear or get duplicated unexpectedly
- App crashes on iOS 7, 8, and newer versions
- Unable to add or import calendar events
- Map integration crashes app
- Reminder notifications not working
- Syncing issues with multiple calendars
- App becomes unresponsive when editing events
- Location request loops infinitely
- Events not syncing to other calendar apps
- App freezes when changing settings
- Weather temperature unit settings don't work
- Chinese character input not supported
Requested features
18 requests- Push notifications for events and reminders
- Color coding for different calendars
- Search functionality for events
- Facebook birthday integration
- Natural language event input
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- iPad version
- Dark mode/additional themes
- Ability to change week start day (Monday vs Sunday)
- Google Calendar sync
- Event invitation and RSVP functionality
- Drag and drop event management
- Badge notification with current date
- Celsius temperature option
- Desktop/Mac version
- Notes and image attachments for events
- Russian, German, Chinese language support
- Customizable default view on app launch
- Double-click day to open event list
Calendars
Reported bugs
3 issues- Disappearing events and appointments
- Upgrade process causing data loss
- Freezing and crashing on certain devices
Requested features
5 requests- Recurring events for free users
- Customizable widgets and app icons
- Ability to archive/restore past events
- Improved Apple Watch integration
- Shared calendars and family management
In-app purchases
Caleido (formerly Event Book)
No in-app purchases
Calendars
- Calendars PRO 1 Month$3.991 Month
- Calendars by Readdle: Interesting Calendars1 Month trial$3.991 Year
- Calendars PRO 1 Month7 Days trial$3.991 Month
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- Calendars PRO 1 Year7 Days trial$19.991 Year
- Calendars PRO 1 Year1 Year trial$19.991 Year
- Calendars PRO 1 Year7 Days trial$21.991 Year
- Smart Input Upgrade$1.99
- My schedule planner, Organizer$6.99
- Full Pack$12.99
Show 1 moreShow fewer
- Recurring Events$31.99
Questions
Is Caleido (formerly Event Book) free?
Is Calendars free?
Which has better reviews, Caleido (formerly Event Book) or Calendars?
Do Caleido (formerly Event Book) or Calendars have ads?
Which is updated more often, Caleido (formerly Event Book) or Calendars?
Other comparisons
