Proton Proton Calendar: customer experiences
Reviewers report mixed experiences with Proton Calendar, with roughly equal numbers of positive and negative mentions, 762 positive and 783 negative out of 2,122 total. The overall sentiment has remained relatively stable over time, hovering around a 3.3-star average across 2025 and 2026, with minor fluctuations. While many users appreciate the app’s privacy focus and clean design, recurring complaints center on missing core features, poor integration with device calendars, and restrictive free-tier limitations. The app’s usability has not improved significantly in recent months, and some users have reported regression, such as broken widgets and lost event access. Despite these issues, a consistent group of users values the app’s security and visual appeal, suggesting that privacy remains a key draw even when functionality falls short.
What customers praise
Users frequently praise Proton Calendar for its strong privacy protections and clean, modern interface. Many highlight that the app feels secure and trustworthy, especially compared to mainstream alternatives. The visual design and smooth performance are often noted as positives, with some reviewers calling it 'fantastic' and 'very well-designed.' The app’s commitment to user data privacy is a consistent reason for continued use, even when other features are lacking.
What customers said:
- „plus security and privacy“
- „A fantastic and privacy-friendly calendar app“
- „Visually very well done, runs nice and smoothly.“
„Visually very well done, runs nice and smoothly.“
Original„Optisch sehr gelungen, läuft schön flüssig.“
Common complaints
Common complaints include the lack of basic calendar features such as custom event colors, search functionality, and support for recurring events on variable dates like the second Sunday of a month. Several users report that the app fails to automatically adjust to local time zones when accepting invitations, requiring manual fixes. The absence of a functional widget and the need to sign in even for basic use are also frequently criticized. Some users feel the app is underdeveloped, with outdated functionality and poor integration with Android’s native calendar system.
What customers said:
- „You can change it manually from settings menu, but I'd rather have it set as default.“
- „which is one of the most basic features that a digital calendar requires to be more…“
„which is one of the most basic features that a digital calendar requires to be more efficient“
- „The app doesn’t allow a yearly event on say the 2nd sunday in a given month.“
How it has changed over time
Over time, Proton Calendar has seen little meaningful improvement. Ratings have fluctuated slightly but remained mostly stagnant, with no clear upward trend. The app’s core issues, such as missing features and poor device integration, have persisted across multiple months. Some users reported that features like the widget stopped working, and others noted that the app appears unchanged despite user feedback. The lack of updates and responsiveness to feature requests has led to frustration, with some calling the app 'stuck in 2005.'
What customers said:
- „I don’t think any of their apps have had an update.“
- „the widget is no longer working“
- „It makes no sense to have to load events every time the application is started.“
„It makes no sense to have to load events every time the application is started.“
Original„não faz sentido ter de carregar os eventos sempre que a aplicação é iniciada“
Practical takeaways
For users prioritizing privacy, Proton Calendar remains a viable option despite its flaws. However, those needing reliable functionality, like recurring events, search, or color customization, may find it inadequate. The lack of standalone pricing and the requirement to pay for the full Proton suite to access basic features is a major barrier. Users should consider whether the privacy benefits outweigh the usability limitations, especially if they rely on calendar features for work or personal organization.
What customers said:
- „the free version doesn't allow custom color for events“
- „the payment system is kinda slimy too“
- „how crazy is it that we don't have checkbox functionality yet?“
Over time
Data as table
| Month | Avg. rating | Count |
|---|---|---|
| 2025-09 | 3.35 | 79 |
| 2025-10 | 3.51 | 86 |
| 2025-11 | 3.19 | 86 |
| 2025-12 | 3.22 | 86 |
| 2026-01 | 3.38 | 80 |
| 2026-02 | 3.27 | 104 |
| 2026-03 | 3.35 | 109 |
| 2026-04 | 3.11 | 112 |
| 2026-05 | 3.29 | 136 |
| 2026-06 | 3.28 | 99 |
| 2026-07 | 3.39 | 116 |
| 2026-08 | 3.48 | 27 |
Sentiment over time
Data as table
| Month | Positive | Neutral | Negative | Count |
|---|---|---|---|---|
| 2025-09 | 33% | 34% | 33% | 79 |
| 2025-10 | 47% | 22% | 31% | 86 |
| 2025-11 | 33% | 20% | 48% | 86 |
| 2025-12 | 33% | 28% | 40% | 86 |
| 2026-01 | 38% | 33% | 30% | 80 |
| 2026-02 | 39% | 30% | 31% | 104 |
| 2026-03 | 34% | 28% | 39% | 109 |
| 2026-04 | 27% | 33% | 40% | 112 |
| 2026-05 | 40% | 18% | 42% | 136 |
| 2026-06 | 35% | 25% | 39% | 99 |
| 2026-07 | 38% | 30% | 32% | 110 |
| 2026-08 | 53% | 29% | 18% | 17 |
Customer voices
Short excerpts - full reviews are available at the original source.
„The app is unable to adjust to local time zone after accepting calendar invitations from proton mail.“
„Proton gives me the convenience of a digital calendar“
„doesn't use Android's Calendar API“
„It lacks the ability to search for events within the calendar.“
„It would be greatly appreciated, and make adding come holidays to the calendar easier.“
„I gave it 3 stars because it isnt fully functional and have gone back to apple calendar which does provide this feature.“
„a fine comprimise for zero knowledge personal and shared calendars“
„Good calendar app, but needs more functions.“
What Reddit users discuss
Below are extracts from Reddit which discuss Proton Calendar in more detail - each linked to the original thread.
„Proton Calendar is, without a doubt, one of the most solid solutions for those who want to protect their privacy.“
„Right now Proton Calendar feels unfinished“
„The calendar is driving me nuts.“
„Proton's Mail & Calendar combination is just not good“
„we are currently rebuilding Proton Calendar from the ground up across iOS, Android, and Web.“
Cite this page
Citatio (2026). Proton Proton Calendar: customer reviews 2026. Retrieved 18 August 2026 from https://citatio.ai/proton-reviews/products/proton-calendar/
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