Comparison

iPGMail vs K4us German Keyboard

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

Head to head
About

iPGMail

This app simplifies PGP encryption for iOS users, allowing easy sending and receiving of encrypted emails and files. It supports the OpenPGP standard, key management, and various import methods for keys and messages.

Highlights
  • PGP encryption and decryption
  • Send and receive encrypted emails
  • Encrypt and decrypt files
  • Create and manage PGP keys
  • Import keys from various sources
  • Supports OpenPGP standard
Features
Read full description

iPGMail is a complete OpenPGP client for iPhone and iPad. Encrypt, decrypt, and digitally sign email and files using the same RFC 9580 / RFC 4880 standard you already use with GnuPG, Mailvelope, Thunderbird, ProtonMail's PGP exports, and any other OpenPGP-compatible tool. Bring your existing PGP identity to iOS or generate a new one in the app. Your private keys are stored in a private local database with the highest data-protection class and are unlocked only by Touch ID or Face ID. All cryptography runs locally — your keys and message content never leave your device. CRYPTO & INTEROPERABILITY • OpenPGP v4 and v6 (RFC 9580 / RFC 4880, RFC 6637) — fully interoperable with GnuPG, Mailvelope, Thunderbird, ProtonMail PGP exports, and any other compliant tool • Post-quantum encryption (RFC 9980): import, encrypt to, and verify signatures from hybrid ML-KEM + ML-DSA keys, which pair NIST-standardized post-quantum algorithms with proven elliptic-curve cryptography • Optional post-quantum key generation: create v6 ML-DSA-65 + ML-KEM-768 or ML-DSA-87 + ML-KEM-1024 keys (turn on in Settings › Advanced) • Public-key algorithms: RSA, DSA, ECDSA, EdDSA (Ed25519, Ed448), ECDH (Curve25519, X448), ML-KEM, ML-DSA • Symmetric ciphers including AES-256, with modern AEAD encryption on PGP v6 (SEIPDv2) messages • PGP/MIME for encrypted email; standard ASCII-armored output for any plain-text channel • Detached and inline signatures; sign-only mode for authenticated but readable messages • Symmetric (password-based) file encryption • Encrypt to multiple recipients in a single message, mixing classic and post-quantum keys EMAIL • Send encrypted email directly from the app via SMTP — works with iCloud, Gmail, Outlook / Hotmail, Yahoo, AOL, Fastmail, GMX, Yandex, mail.ru, QQ, Comcast, and any custom SMTP server • Google OAuth2 for password-free Gmail authentication • Reply with quoted plaintext ("> " prefix) so encrypted threads read like normal email • Or hand off to your default mail app via the standard iOS share sheet KEY MANAGEMENT • Generate new keypairs in-app with strong defaults (ECC or RSA) • Import existing public and private keys (ASCII-armored or binary) • Search SKS / hkps key servers and Keybase to find recipient keys • Attach your public key to outgoing messages so recipients can import it directly • Inspect key flags, expiration, signatures, and user IDs FILES • Encrypt and decrypt files up to 100 MB per file (200 MB total per message), with on-screen progress • Quick Look preview of decrypted content in-place • Receive encrypted attachments directly from iOS Mail.app — no copy/paste required • Read .pgp, .gpg, .asc, and .sig files from anywhere via the Files app, AirDrop, iCloud Drive, Dropbox, or the system clipboard • Open URL handler for the x-ipgmail:// scheme so other apps can hand work to iPGMail iPAD-OPTIMIZED • Sidebar navigation and full keyboard shortcut support • Optimized layouts for Split View and Stage Manager PRIVACY POSTURE • Private keys are stored locally in a secured private database and unlocked only by Touch ID / Face ID • All encryption, decryption, signing, and verification happens on-device • No account creation, no cloud middleman, no third-party access to your message content • Open standard — your keys and messages stay portable to any other OpenPGP tool, on any platform WHO IT'S FOR Built for journalists, activists, security professionals, lawyers, developers, and anyone who already uses PGP on the desktop and wants the same workflow on iOS. Bring your existing key, decrypt your inbox, sign and send — without surrendering custody of your keys to anyone.

About

K4us German Keyboard

Read full description

For iPhone User please try "AEI Keyboard Note" App. (This app is Free) Original German Keyboard for iPhone & iPad * With Arrow Keys * Ideal Key for iPhone * Easy to input “ä Ä ö Ö ü Ü ß" * iPad Special Ten Keys like PC Ten Keys. Useful keyboard Settings (tap"tools") You can turn off Key Sound from it. Please add this Keyboard from iOS Setting and switch "Allow Full Access" Note : This app may not work on Old Apps.

Screenshots

iPGMail4 screens
K4us German Keyboard4 screens

Verdict

The call

The clearest difference is update cadence: iPGMail at every 10 days against K4us German Keyboard's every 19 months. K4us German Keyboard's advantage is price ($0.99 vs $3.99) and iOS requirement (15.6 vs 17.0). On ads, in-app purchases 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

iPGMail costs $3.99 and K4us German Keyboard $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

iPGMail ships an update every 10 days, K4us German Keyboard every 19 months. The most recent releases landed on October 19, 2026 and October 14, 2026 respectively.

Scorecard3 real differences · 7 level
iPGMail versus K4us German Keyboard: the parameters behind the verdict, then further details
ParameteriPGMailK4us German Keyboard
Price$3.99$0.99 — better
Rating4.3 (235 ratings) — better—
Positive reviews67.2% of reviews—
Number of ratings235 — better—
Update frequencyEvery 10 days — betterEvery 19 months
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS17.015.6 — better
Further details — not scored
Size24 MB3 MB
Age rating4+4+
DeveloperWyllys Ingersoll4us

Bugs and requests

iPGMail

Reported bugs

3 issues
  • Crashes when importing certain private keys
  • Issues with sending/receiving encrypted attachments
  • Problems with key server integration and key management

Requested features

4 requests
  • Ability to save password/passphrase
  • Automatic deletion of local decrypted files
  • Better integration with iOS Mail app
  • Support for more encryption algorithms beyond RSA

K4us German Keyboard

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

iPGMail

No in-app purchases

None

K4us German Keyboard

No in-app purchases

Questions

Is iPGMail free?
iPGMail costs $3.99, with no in-app purchases.
Is K4us German Keyboard free?
K4us German Keyboard costs $0.99, with no in-app purchases.
Do iPGMail or K4us German Keyboard have ads?
Neither iPGMail nor K4us German Keyboard shows ads.
Which is updated more often, iPGMail or K4us German Keyboard?
iPGMail ships an update every 10 days, and K4us German Keyboard every 19 months. Most recently, iPGMail was updated on October 19, 2026 and K4us German Keyboard on October 14, 2026.

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