Skip to content
StateMaps

Is Proton Calendar Safe?

Proton Calendar privacy label · by Proton AG · checked November 2026

  • Nothing linked to you
App Privacy label Developer-reported · checked November 1, 2026
Used to track you
0types

None declared

Linked to you
0types

None declared

Not linked to you
1type
Short answer

On the label it is low-risk: Proton Calendar collects some data but says none of it is linked to you or used for tracking. None of it falls in Apple's most sensitive categories (health, financial, location, contacts or your own content). In total the label lists 1 data type; 28% of secure email apps we checked declare tracking.

At a glance

Proton Calendar privacy in one look

Data exposure on the label
Not linked to you
  1. 1
  2. 2
  3. 3
  4. 4

Built only from the developer's App Store label. It describes disclosure, not tested behaviour.

Verdict from the label
Not linked to you

Proton Calendar collects some data but says none of it is linked to your identity, and none is used for tracking.

Try it

Did Proton Calendar ask for something?

Pick the permission prompt you saw. We compare it with what Proton Calendar's developer declared.

It asked me for access to…
Tap a prompt to compare it with the label.
Not on the label

Location is not on Proton Calendar's label. That can be fine: data used only on your iPhone does not have to be declared. If the data would need to leave the phone for the feature to work, ask why it is missing.

Not on the label

User Content is not on Proton Calendar's label. That can be fine: data used only on your iPhone does not have to be declared. If the data would need to leave the phone for the feature to work, ask why it is missing.

Not on the label

Contacts is not on Proton Calendar's label. That can be fine: data used only on your iPhone does not have to be declared. If the data would need to leave the phone for the feature to work, ask why it is missing.

Not declared on the label

Proton Calendar declares no tracking, so a tracking prompt would contradict its label. Decline it, and consider reporting the mismatch to Apple.

Not on the label

Health & Fitness is not on Proton Calendar's label. That can be fine: data used only on your iPhone does not have to be declared. If the data would need to leave the phone for the feature to work, ask why it is missing.

A permission is what the app can reach on your iPhone; the label is what the developer says leaves it. They answer different questions.

Line by line

What Proton Calendar collects, explained

Data typeWhat it coversWhere to limit it
DiagnosticsNot linked to you Crash logs, launch times, hang rates and energy use. Settings › Privacy & Security › Analytics & Improvements › Share With App Developers controls what Apple passes on; the app's own crash reporting is separate.
Reading the label

What Proton Calendar's label means for you

Proton Calendar's label has 1 type under “Data Not Linked to You”. A data type can appear in more than one section when it is used for different purposes — for example, identifiers used for both analytics and advertising.

Every type on Proton Calendar's label is in the “not linked” section, so the developer says the data is stripped of anything that identifies you before it is used. That is typical of anonymous analytics and crash reporting. Not linked is still collected: the data leaves your phone.

None of the data types fall into the categories most people consider sensitive: health, financial information, precise location, contacts, browsing history or the content you create.

Email apps see every message and contact. Third-party mail clients may route mail through their own servers to offer features like push or AI summaries. Check whether the client connects to your provider directly or stores your mail on its servers.

Among the 141 secure email apps in our snapshot with a label, 28% declare tracking, 60% collect data linked to you and 23% say they collect nothing. Proton Calendar lists 1 data type, fewer than the average of 2.9 for this group.

Productivity apps tend to collect the work you do in them — documents, notes and files — so User Content is common. The question is whether it syncs to the developer's servers and how it is protected there.

On your iPhone

Settings to check for Proton Calendar

  1. 1

    Lock the app

    On iOS 18 and later, touch and hold the icon and choose Require Face ID. Anyone who picks up your unlocked phone then needs your face, fingerprint or passcode to open it.

  2. 2

    Notifications

    Settings › Notifications › Proton Calendar › Show Previews: When Unlocked keeps message and account details off the Lock Screen.

Cross-app tracking

Does Proton Calendar track you?

No tracking declared

There is no “Data Used to Track You” section on Proton Calendar's label.

Does Proton Calendar track you? Full answer and how to stop it →

iOS 18 and later

Lock Proton Calendar behind Face ID

  1. Find Proton Calendar on your Home Screen or in App Library.
  2. Touch and hold the icon until the quick-actions menu opens.
  3. Tap Require Face ID (or Require Touch ID / Require Passcode, depending on your iPhone).
  4. Tap Require Face ID again to confirm. Proton Calendar now asks for authentication every time it opens.

The lock is an iPhone feature, so it works whether or not Proton Calendar has a passcode of its own. It does not change what the app sends to its developer.

Lock or hide Proton Calendar: step-by-step guide →

From the App Store record

About Proton Calendar

DeveloperProton AG
App Store categoryProductivity (also Utilities)
Latest version2.25.1, released June 2026
First releasedNovember 2022
RequiresiOS 16.0 or later
Size185 MB
Age rating4+
Languages26 (BE, CA, CS, DA, NL, EN, FI, FR…)
Bundle IDch.protonmail.calendar

The current version shipped in June 2026. That is recent enough that the label should reflect current practices, but check the App Store page again before relying on it.

Also by Proton AG: Proton Pass, Proton Authenticator & 2FA, Proton Drive, Encrypted Email, Proton VPN, SimpleLogin.

Read with care

What the label cannot tell you

  • A label is self-reported. Apple publishes the developer's answers and can reject apps that misrepresent them, but it does not independently verify what Proton Calendar sends.
  • It does not say where data is stored, how long it is kept, whether it is encrypted, or which companies receive it. The privacy policy covers those points.
  • Optional data counts: if a feature lets you add something (a profile photo, a phone number), the type is listed even if you never use the feature.
  • Data handled only on your iPhone is not 'collected', so a no-collection label is compatible with an app that reads your files locally.
  • Third-party sign-in, payment processors and SDKs are supposed to be included, but a label can lag behind a new version.

The question to ask Proton Calendar's developer: Does my email pass through the app maker's servers?

How it compares

Proton Calendar vs similar secure email apps

Data types listed on each App Store privacy label
Tracks youLinked to youNot linkedCollects nothing

Fewer types is not automatically safer: a cloud backup app has to collect your files to work. Compare like with like.

Checking another app?

Look up any of our apps in seconds, or put two labels side by side.

App privacy checkerCompare two appsBrowse 4,500 apps
Keep exploring

Apps similar to Proton Calendar

Ivanti Email
Not linked4 types
Evap Mail
Tracks you3 types
Temp Mail - Temporary Email
Collects nothing
Temp Mail - Temporary Mail Box
Tracks you4 types
MobiVisor Secure Exchange
Collects nothing
Inbox Pro
Collects nothing
ISEC7 MAIL
Not linked2 types
Secria Mail
Collects nothing

All secure email apps → Who tracks you? A–Z → Apps that collect diagnostics → Privacy label decoder →

Do it now

Your Proton Calendar privacy checklist

Tick what you have done
Tick each step as you do it on your iPhone.

Done. You have applied every control the label points to.

Quick quiz

True or false?

  1. Q1Proton Calendar's privacy label says it uses data to track you.
    Right.
    Not quite.

    False: there is no Data Used to Track You section on Proton Calendar's label.

  2. Q2Apple tests every app to confirm its privacy label is accurate.
    Right.
    Not quite.

    Labels are self-reported by developers. Apple can reject or remove apps that misrepresent practices, but it does not audit each label.

  3. Q3Proton Calendar collects Diagnostics.
    Right.
    Not quite.

    True: Diagnostics appears on its label, in the Not Linked to You section.

  4. Q4Data “Not Linked to You” is never sent off your iPhone.
    Right.
    Not quite.

    It is collected and sent; the developer says it is de-identified rather than tied to your account or device.

  5. Q5Tapping “Ask App Not to Track” can stop an app from working.
    Right.
    Not quite.

    Apple's rules require apps to work the same whether or not you allow tracking.

Questions people ask

Proton Calendar privacy FAQ

Is Proton Calendar safe to use?
Based on its App Store privacy label, proton Calendar collects some data but says none of it is linked to your identity, and none is used for tracking. Whether that is acceptable depends on what you will store in it. The label is developer-reported, not an independent security test.
Does Proton Calendar track you?
No. Proton Calendar's label has no Data Used to Track You section.
What data does Proton Calendar collect?
Diagnostics. None of it is linked to your identity.
Who makes Proton Calendar?
Proton AG, according to the App Store. It was first released in November 2022 and the current version is 2.25.1.
Can I lock Proton Calendar with Face ID?
On iOS 18 or later, touch and hold Proton Calendar's icon and choose Require Face ID (or Touch ID / Passcode). This is an iPhone feature and works for most downloaded apps, whether or not the app has its own lock.
How does Proton Calendar compare with other secure email apps?
Across 141 secure email apps with labels in our snapshot, 28% declare tracking and 23% say they collect no data. Proton Calendar lists 1 data type against an average of 2.9.
Does my email pass through the app maker's servers?
The privacy label cannot answer that. Look for it in Proton Calendar's privacy policy or support pages, linked from the App Store listing. Check whether the client connects to your provider directly or stores your mail on its servers.
How do I delete my data from Proton Calendar?
Apps that let you create an account must also let you start account deletion from inside the app (an App Store rule since June 2022). Deleting the app from your iPhone alone does not delete data already sent to the developer.
Facts on this page come from Proton Calendar on the App Store, as reported by the developer. Checked 2026-11-01. How we collect data · Report a correction