Comparison

SMTPTester vs Shell Keyboard

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

Head to head
About

SMTPTester

This tool allows users to test SMTP server functionality by sending emails. It helps identify and log any errors encountered during the testing process.

Highlights
  • SMTP server testing
  • Email sending
  • Error logging
  • Server address input
  • User information input
Features
Read full description

SMTPTester is an SMTP service test tool, through which you can fill in the server address, user information, and then send mail, if there is an error, you can log

About

Shell Keyboard

Features
Read full description

Shell Keyboard adds the keys a terminal actually needs — the ones iOS's default keyboard leaves out. Working over SSH or in a local shell needs Ctrl, Esc, Tab, arrow keys, and function keys, none of which exist on the standard iOS keyboard. Shell Keyboard is a custom keyboard built specifically for terminal apps like Blink, Termius, Prompt, a-Shell and iSH — it sends the exact ASCII control codes and ANSI/VT escape sequences your terminal expects, the same bytes a physical keyboard would send. NEW ON IPAD: A REAL KEYBOARD Choose a 60% or 75% layout, the compact keyboards terminal users already type on. The 75% layout puts Esc, F1–F12, a number row, Caps Lock, Home, End, Page Up, Page Down and inverted-T arrow keys on one screen, and Shift types the symbol printed on each key, just like a physical keyboard. The 60% layout keeps the function keys, navigation and arrows one fn press away. iPad opens in the 75% layout; the original ShellKey layout is one tap away in Settings. WHAT'S INCLUDED • A dedicated terminal layer: Ctrl, Alt, Esc, Tab, arrow keys, Home/End/PgUp/PgDn, and the punctuation a shell prompt uses constantly • Ctrl and Alt as proper modifiers — latch one for a single keypress, or double-tap to lock it on, like a hardware keyboard • A full function-key layer: tap fn and the top row becomes F1 through F12, while every other row stays exactly where it was • Arrow keys that match the app you're in — Normal for shells, Application for vim, tmux, less and htop, or Move the Cursor for ordinary text fields • Return or Enter: long-press the Return key to switch between a carriage return and a line feed • A plain QWERTY layer and a complete symbols layer, for ordinary text — hostnames, paths, commit messages — without leaving the keyboard • Seven themes — Shell, Ember, Glacier, Dusk, Moss, Void (pure black) and High Contrast — each in light and dark, and an Appearance option to keep the keyboard light or dark everywhere • On iPad, 60% and 75% layouts (75% by default), described above • A searchable reference inside the app, listing every key alongside the exact escape sequence and hex bytes it sends • Every key emits the exact byte sequence a real terminal expects SETTINGS LIVE IN THE KEYBOARD Touch and hold the key with the small gear (or tap the gear key on the iPad's 60% and 75% layouts) for Haptic feedback, Theme, Appearance and, on iPad, Layout. They live in the keyboard itself because, without Full Access, iOS keeps a keyboard and its app apart, and Shell Keyboard never asks for Full Access. BUILT FOR PRIVACY Shell Keyboard never asks for Full Access. It cannot reach the network. It never reads, stores, or transmits anything you type — every key it sends is decided from the key you tapped, and nothing else. No analytics, no crash reporting, no account. GOOD TO KNOW In a terminal or editor running inside a web browser — code-server, Jupyter and the like — the keys that send a multi-character escape sequence don't get through: the arrow keys, F1 through F12, Home, End, Page Up, Page Down, Shift+Tab and Alt combinations. Everything that sends a single byte works there normally, including every Ctrl combination, Esc, Tab, Return and ordinary typing. Web pages listen for key press events and iOS only lets a keyboard extension insert text, so this is an iOS limitation that applies to every third-party keyboard, not something an app can work around. WHO IT'S FOR Anyone who SSHes from an iPhone or iPad — sysadmins, developers, and anyone tired of missing Ctrl+C.

Screenshots

SMTPTester2 screens
Shell Keyboard4 screens

Verdict

The call

The clearest difference is rating: Shell Keyboard at 5.0 against SMTPTester's 1.0. Shell Keyboard also leads on update cadence (fortnightly vs every 11 months) and chart position (#17 vs #154). SMTPTester's advantage is device support (4 vs 2) and iOS requirement (11.0 vs 16.0). On price, ratings volume, ads and in-app purchases 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

SMTPTester costs $0.99 and Shell Keyboard $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Shell Keyboard holds the better App Store score, 5.0 against 1.0. Both are backed by a comparable volume of ratings — 1 and 1 respectively.

UpkeepUpdate frequency

SMTPTester ships an update every 11 months, Shell Keyboard fortnightly. The most recent releases landed on October 25, 2026 and October 24, 2026 respectively.

Scorecard5 real differences · 6 level
SMTPTester versus Shell Keyboard: the parameters behind the verdict, then further details
ParameterSMTPTesterShell Keyboard
Price$0.99$0.99
Rating1.0 (1 ratings)5.0 (1 ratings) — better
Positive reviews20.0% of reviews—
Number of ratings11
Update frequencyEvery 11 monthsFortnightly — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaid—
Best chart rank#154#17 — better
DevicesiPhone, iPad, iPod, Mac — betteriPhone, iPad
Requires iOS11.0 — better16.0
Further details — not scored
Size25 MB3 MB
Age rating4+4+
Developer峰 高Nguyen Nguyen

In-app purchases

None

SMTPTester

No in-app purchases

None

Shell Keyboard

No in-app purchases

Questions

Is SMTPTester free?
SMTPTester costs $0.99, with no in-app purchases.
Is Shell Keyboard free?
Shell Keyboard costs $0.99, with no in-app purchases.
Which has better reviews, SMTPTester or Shell Keyboard?
Shell Keyboard is rated higher. SMTPTester averages 1.0 out of 5 from 1 ratings, while Shell Keyboard averages 5.0 from 1 ratings.
Do SMTPTester or Shell Keyboard have ads?
Neither SMTPTester nor Shell Keyboard shows ads.
Which is updated more often, SMTPTester or Shell Keyboard?
SMTPTester ships an update every 11 months, and Shell Keyboard fortnightly. Most recently, SMTPTester was updated on October 25, 2026 and Shell Keyboard on October 24, 2026.
Which is more popular, SMTPTester or Shell Keyboard?
SMTPTester currently peaks at #154 in the App Store charts, and Shell Keyboard at #17. Chart position reflects recent download velocity rather than total install base.

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