Comparison

HiCal vs One Calendar

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

Head to head
About

HiCal

This app facilitates collaborative event planning and scheduling for groups. Share timetables, receive real-time updates on changes, and communicate via comments. Ideal for students, project teams, and organizations to stay synchronized.

Highlights
  • Group event scheduling
  • Real-time push notifications
  • Event comments and discussion
  • Shared timetables
  • Private and public groups
  • Event repetition support
Read full description

Organize yourselves for your classes, projects, or company with HiCal, the collaborative calendar! Create or join your class’ or club’s group, and get your shared timetable in your pocket. You can be part of multiple groups. You will receive Push notifications each time that a group’s event is modified, or an event is commented. Event repetition is supported (including “once every two weeks”). HiCal helps you to organize yourself and to collaborate with your friends and colleagues in different situations: - Students and pupils: Add comments to a lesson at a given day, to indicate homework and exams for example, and they will instantly be synced across smartphones and tablets, and shared with your class. You will not ever ask yourself again what is left to do: the answer will be in your pocket, up-to-date, at any moment. Even if only one person indicates the exams to come, everyone will be aware: one for all, and all for one! - Projects: Determine deadlines with your teammates, and discuss them in the comments! Your project is a secret? Then create a secret group, which will be hidden from the group search results. Only the people you add will be able to join the group. - Companies, clubs and organizations: Write down meetings’ or activities’ dates and locations, suggest or edit in real time, and instantly update all your fellows of a schedule change, thanks to push notifications. - Organize public events: Create a group, open to everyone, to let people stay tuned about your upcoming events! In this kind of group, only the group’s administrators can create or edit events. Thus, you can share your events, your live sessions for example if you’re a band, while keeping control. And if something unexpected happens, you can inform group’s members thanks to comments and push notifications! - Education: If you are an educational institution (school, college, university...), you can also use HiCal, by creating a group for each class or course, and inviting your students in them. Simplify your teachers’ and students’ life with HiCal!

About

One Calendar

Consolidate all your digital calendars into a single, easy-to-read view. Manage appointments, events, and birthdays from various providers like Google, Outlook, iCloud, and more, all within one application.

Highlights
  • Integrates multiple calendar providers
  • Easy-to-read overview
  • Manage appointments and events
  • View birthdays
  • Cross-platform availability
Features
Read full description

The most popular app to view all your calendars like Google, Live, Outlook, iCloud, Exchange, Office365, Yahoo, Nextcloud, Synology, GMX, Mailbox.org, ownCloud and more. OneCalendar integrates all your calendars into an easy-to-read overview. View and manage all your appointments, events and birthdays. OneCalendar is available on all platforms.

Screenshots

HiCal4 screens
One Calendar4 screens

Verdict

The call

The clearest difference is in-app purchases: HiCal at none against One Calendar's 1. HiCal also leads on iOS requirement (13.0 vs 15.0). One Calendar's advantage is review sentiment (81% vs 55%) and ratings volume (21K vs 25). On price, rating, 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

Both are free to download. One Calendar sells 1 one-off in-app purchase. HiCal asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.8 for HiCal against 4.8 for One Calendar. That said, the two scores are not equally well evidenced: One Calendar has 21K ratings behind it against 25, so its average is the more settled of the two. Written reviews are what separate them: 55% of HiCal's written reviews are positive against 81% of One Calendar's.

UpkeepUpdate frequency

HiCal ships an update every 2 months, One Calendar fortnightly. The most recent releases landed on October 21, 2026 and October 29, 2026 respectively.

Scorecard6 real differences · 4 level
HiCal versus One Calendar: the parameters behind the verdict, then further details
ParameterHiCalOne Calendar
PriceFreeFree
Rating4.8 (25 ratings) — better4.8 (21K ratings)
Positive reviews55.0% of reviews80.7% of reviews — better
Number of ratings2521K — better
Update frequencyEvery 2 monthsFortnightly — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod, Mac — better
Requires iOS13.0 — better15.0
Further details — not scored
Size3 MB89 MB
Age rating4+12+
DeveloperNakagawa YugoCode Spark

Customer experience

HiCal

All ratings23 ratings
Positive91.3%
Neutral4.3%
Negative4.3%
Written reviews20 reviews
Positive55.0%
Neutral10.0%
Negative35.0%

One Calendar

All ratings20,632 ratings
Positive95.4%
Neutral3.2%
Negative1.4%
Written reviews830 reviews
Positive80.7%
Neutral8.6%
Negative10.7%

Bugs and requests

HiCal

Not enough reviews yet to summarise bugs or requests.

One Calendar

Reported bugs

5 issues
  • Sync errors
  • Unresponsive buttons
  • Incorrect time zone display
  • Duplicate events
  • Inability to delete future occurrences of recurring events

Requested features

6 requests
  • Multiple reminders for events
  • Ability to edit recurring events
  • Option to change event calendar after creation
  • Printing support
  • More customization options
Show 1 more
  • Widgets for better visibility

In-app purchases

None

HiCal

No in-app purchases

1 purchases

One Calendar

One-time1
  • OneCalendar premium$5.99

Questions

Is HiCal free?
HiCal is free to download, with no in-app purchases.
Is One Calendar free?
One Calendar is free to download, with in-app purchases available.
Which has better reviews, HiCal or One Calendar?
HiCal is rated higher. HiCal averages 4.8 out of 5 from 25 ratings, while One Calendar averages 4.8 from 21K ratings.
Do HiCal or One Calendar have ads?
Neither HiCal nor One Calendar shows ads.
Which is updated more often, HiCal or One Calendar?
HiCal ships an update every 2 months, and One Calendar fortnightly. Most recently, HiCal was updated on October 21, 2026 and One Calendar on October 29, 2026.

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