Comparison

Proton Mail vs Pi Epsilon

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

Head to head
About

Proton Mail

This encrypted email service from Switzerland prioritizes user privacy with end-to-end encryption. It offers robust security features to protect your communications from phishing, spam, and tracking, allowing you to manage your inbox with ease.

Highlights
  • End-to-end encryption
  • Password-protected emails
  • Multiple account support
  • Inbox organization (folders, labels)
  • Dark mode
  • Phishing and spam protection
Read full description

Keep your conversations private. Proton Mail is encrypted email from Switzerland. Used by millions worldwide, our all-new email app protects your communications and has everything you need to easily manage your inbox. The Wall Street Journal says: “Proton Mail offers encrypted email, which makes it virtually impossible for anyone to read it except the sender and the recipient.” With the all-new Proton Mail app, you can: • Create a @proton.me or @protonmail.com email address • Send and receive encrypted emails and attachments with ease • Switch between multiple Proton Mail accounts • Easily manage your email with conversations • Keep your inbox tidy and clean with folders, labels and simple swipe-gestures • Receive new email notifications • Send Password-protected Emails to anyone • Keep important emails in focus with automatic, private categories • Enjoy your inbox in dark mode Why use Proton Mail? • Easy to use — Our all-new app has been redesigned to make it easier to read, organize, and write your emails. • Your inbox is yours — We don’t spy on your communications to show you targeted ads. Your inbox, your rules. • Rigorous encryption — Your entire inbox is secured, on all your devices. No one can read your emails but you. Proton is privacy, guaranteed by end-to-end and zero-access encryption. • Unmatched protection — We offer strong phishing, spam, and spying/tracking protection for all your communications. Industry Leading Security Features Messages are stored on Proton Mail servers using end-to-end encryption at all times and are transmitted securely between Proton servers and user devices. This largely eliminates the risk of message interception. Zero Access to Your Email Content Proton Mail's zero access architecture means that your data is encrypted in a way that makes it inaccessible to us. Data is encrypted on the client side using an encryption key that Proton does not have access to. This means we don't have the technical ability to decrypt your messages. Open-Source Cryptography Proton Mail's open-source software has been thoroughly vetted by security experts from around the world to ensure the highest levels of protection. Proton Mail only uses secure implementations of AES, RSA, along with OpenPGP, while all of the cryptographic libraries used are open source. By using open-source libraries, Proton Mail can guarantee that the encryption algorithms used do not have clandestinely built-in back doors. Proton Mail in the press: “Proton Mail is a Gmail-like email system which uses end-to-end encryption, making it impossible for outside parties to monitor.” Forbes “A new email service being developed by a group who met at MIT and CERN promises to bring secure, encrypted email to the masses and keep sensitive information away from prying eyes.” Huffington Post Follow Proton on social media for all the latest news and offers: Facebook: /proton Twitter: @protonprivacy Reddit: /protonmail Instagram: /protonprivacy Our open-source code base: https://github.com/ProtonMail EULA: http://www.apple.com/legal/itunes/appstore/dev/stdeula

About

Pi Epsilon

A decentralized, anonymous, and end-to-end encrypted communication platform offering voice, text, video, and group calls. It provides robust security features and full user control over the server environment, bypassing third-party providers.

Highlights
  • Decentralized and anonymous communication
  • End-to-end encryption
  • Voice, text, and video calls
  • Group video conferencing
  • User-controlled server hosting
  • Decoy obfuscation tools
Features
Read full description

The Pi Epsilon (Π Ε) Communication Platform is a cutting edge decentralized, anonymous, end-to-end encrypted communication platform that includes voice, text, video, chat, and group video conference calls through a proprietary configuration that bypasses the usage of any third-party provider platforms. The Π Ε communication platform can reside on a dedicated obfuscated Virtual Private Server (VPS) or anywhere, resident to the customer’s location. The Π Ε Communication Platform offers one of the most protective cyber design decoy obfuscation tools from any nefarious attacker looking to obtain information of the real Π Ε communication platform. Look no further for your secure communication needs. Advantages • Decentralized, anonymous, real-time communication, end to end encryption protocol. • Customer has full control and oversite of the communication platform server. • Π Ε can reside on a dedicated Virtual Private Server, private rack server, or a physical server resident within the customer location. • No dependencies of any third-party provider and or backbone infrastructure. • Π Ε resides on a virtual dissimulated encrypted server (VDES), as a decoy obfuscation tool environment, shielding the real IP from any nefarious inquiries. • Π Ε includes voice, text, video, chat, and group video conference. • Supports the federate infrastructure, where multiple instances of Π Ε servers can communicate with each other. • Customer retains Admin console control to manage users, permissions, and resources.

Screenshots

Proton Mail4 screens
Pi Epsilon4 screens

Verdict

The call

The clearest difference is in-app purchases: Pi Epsilon at none against Proton Mail's 6. Pi Epsilon also leads on rating (5.0 vs 4.8) and iOS requirement (15.0 vs 17.2). Proton Mail's advantage is update cadence (every 11 days vs every 6 months) and ratings volume (47K vs 4). 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Proton Mail sells 6 in-app purchases, starting at $5.99 per month. Pi Epsilon asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Pi Epsilon holds the better App Store score, 5.0 against 4.8. That said, the two scores are not equally well evidenced: Proton Mail has 47K ratings behind it against 4, so its average is the more settled of the two.

UpkeepUpdate frequency

Proton Mail ships an update every 11 days, Pi Epsilon every 6 months. The most recent releases landed on September 24, 2026 and September 17, 2026 respectively.

Scorecard7 real differences · 4 level
Proton Mail versus Pi Epsilon: the parameters behind the verdict, then further details
ParameterProton MailPi Epsilon
PriceFreeFree
Rating4.8 (47K ratings)5.0 (4 ratings) — better
Positive reviews46.2% of reviews—
Number of ratings47K — better4
Update frequencyEvery 11 days — betterEvery 6 months
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
Best chart rank#70 — better—
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS17.215.0 — better
Further details — not scored
Size272 MB147 MB
Age rating4+4+
DeveloperProton AGChesapeake International Consulting, LLC

Customer experience

Proton Mail

All ratings47,046 ratings
Positive94.4%
Neutral2.2%
Negative3.5%
Written reviews1,621 reviews
Positive46.2%
Neutral13.6%
Negative40.2%

Pi Epsilon

All ratings4 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

Proton Mail

Reported bugs

3 issues
  • Login issues and lost email data
  • Unreliable push notifications
  • Inconsistent user experience between app and web

Requested features

4 requests
  • Conversation threading and email previews
  • Customizable notification sounds
  • Offline email access
  • Improved syncing across devices

Pi Epsilon

Not enough reviews yet to summarise bugs or requests.

In-app purchases

6 purchases

Proton Mail

Subscriptions4
  • Mail Plus 1 month1 Month trial$5.991 Month
  • Unlimited 1 month$14.991 Month
  • Mail Plus 12 months$47.901 Year
Show 1 more
  • Unlimited 1 year$119.001 Year
One-time2
  • Mail Plus (1 year)$59.99
  • Proton Unlimited$149.99
None

Pi Epsilon

No in-app purchases

Questions

Is Proton Mail free?
Proton Mail is free to download, with in-app purchases available.
Is Pi Epsilon free?
Pi Epsilon is free to download, with no in-app purchases.
Which has better reviews, Proton Mail or Pi Epsilon?
Pi Epsilon is rated higher. Proton Mail averages 4.8 out of 5 from 47K ratings, while Pi Epsilon averages 5.0 from 4 ratings.
Do Proton Mail or Pi Epsilon have ads?
Neither Proton Mail nor Pi Epsilon shows ads.
Which is updated more often, Proton Mail or Pi Epsilon?
Proton Mail ships an update every 11 days, and Pi Epsilon every 6 months. Most recently, Proton Mail was updated on September 24, 2026 and Pi Epsilon on September 17, 2026.

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