Comparison

a vs Syntactic

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

Head to head
About

a

Run a full Unix-like terminal environment on your iOS device. Execute a wide range of commands, edit files, and even program using included interpreters and compilers. Supports multitasking and integration with Shortcuts.

Highlights
  • Local Unix terminal emulator
  • SSH client
  • File transfer (scp, curl)
  • Text editing (vim, ed)
  • Scripting languages (Python, Lua, Perl, JS)
  • C/C++ compiler
  • TeX distribution
Features
Read full description

a-Shell is a complete local terminal emulator, allowing to run most Unix commands on your iOS device. You can transfer files using scp and curl, edit them with vim and ed, process them using grep, awk and sed. You can work with git repositories using lg2.  Most commands are compiled for iOS native Arm64 format, making them fast and well integrated with the BSD Unix that powers iOS/iPadOS. a-Shell includes Python, Lua, Perl, JavaScript, C, C++ for programming and TeX (texlive 2025, with Tikz and LuaTeX) for text processing. There are also multiple network utilities: nslookup, ping, whois, ifconfig... Type help for help, help -l to get the full list of commands. a-Shell can be controlled from Shortcuts: run commands in order, process files in a-Shell, get the results as text or files, transfer files to other apps... a-shell uses iOS 13+ “multiple windows” ability, so you can run multiple shells at the same time, with different commands, in different directories. You can edit a file in one window with vim and process it in the other with python. Compile your C or C++ programs to webAssembly using clang or clang++, and execute the resulting binary. A complete webAssembly SDK is included (WASI-libc). a-Shell is the complete version. If you need a smaller app, and you don't need a C compiler, a TeX engine, or numpy and matplotlib, there is a-Shell mini.

About

Syntactic

Learn and practice Rust programming on your device with a built-in compiler and editor. Includes the Rust Programming Language book, coding challenges, and optional AI error explanations. All features work offline.

Highlights
  • On-device Rust compiler
  • Syntax highlighting editor
  • Rust Programming Language book
  • Runnable code examples
  • Built-in quizzes
  • 66 coding challenges
  • Optional AI error explanations
Features
Read full description

Syntactic is a complete Rust learning environment that runs entirely on your device — a real Rust compiler in your pocket. WRITE AND RUN REAL RUST Write Rust in a fast editor with syntax highlighting, inline errors, and code completion, then compile and run it on-device. No account, no server round-trip, no internet required — the actual Rust compiler runs on your iPhone and iPad. LEARN FROM THE RUST BOOK The complete Rust Programming Language book is built in, formatted for comfortable reading, with runnable examples one tap from the editor. Check your understanding with built-in quizzes as you go. PRACTICE WITH CHALLENGES Sharpen your skills with 66 hands-on coding challenges across three difficulty tiers. Write your solution, tap Submit, and an on-device test suite grades it instantly — with the failing case and your own debug output right there when you need them. EXPLAIN ERRORS WITH ON-DEVICE AI (OPTIONAL) Stuck on a compiler error? An optional on-device AI can explain it in plain language, grounded in your own code — downloaded only if you choose, and running fully offline. EVERYTHING ON-DEVICE Your code never leaves your device. There is no sign-in and no tracking. Compiling, running, reading, and practicing all work completely offline, anywhere. Syntactic is an independent, unofficial app. It is not affiliated with or endorsed by the Rust Foundation.

Screenshots

a4 screens
Syntactic4 screens

Verdict

The call

The clearest difference is monetization model: Syntactic at free against a's paid. Syntactic also leads on rating (5.0 vs 4.6). a's advantage is ratings volume (553 vs 1) and chart position (#19 vs unranked). On price, 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

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Syntactic holds the better App Store score, 5.0 against 4.6. That said, the two scores are not equally well evidenced: a has 553 ratings behind it against 1, so its average is the more settled of the two.

Scorecard5 real differences · 6 level
a versus Syntactic: the parameters behind the verdict, then further details
ParameteraSyntactic
PriceFreeFree
Rating4.6 (553 ratings)5.0 (1 ratings) — better
Positive reviews78.3% of reviews—
Number of ratings553 — better1
Update frequencyMonthly—
AdsNoNo
In-app purchasesNoNo
MonetizationPaidFree — better
Best chart rank#19 — better—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS14.0 — better16.0
Further details — not scored
Size1.9 GB299 MB
Age rating17+4+
DeveloperNicolas HolzschuchTosin Amuda

Customer experience

a

All ratings553 ratings
Positive88.1%
Neutral4.5%
Negative7.4%
Written reviews387 reviews
Positive78.3%
Neutral9.6%
Negative12.1%

Syntactic

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

a

Reported bugs

3 issues
  • Toolbar buttons not accessible in portrait mode on some devices
  • Pasting from clipboard can insert unexpected characters
  • Sourcing certain script files causes crashes

Requested features

5 requests
  • Add support for package managers like Homebrew or APT
  • Implement more advanced shell features like job control and better tab completion
  • Integrate Git for version control
  • Allow installing additional packages and libraries
  • Improve clipboard and file management integration

Syntactic

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

a

No in-app purchases

None

Syntactic

No in-app purchases

Questions

Is a free?
a is free to download, with no in-app purchases.
Is Syntactic free?
Syntactic is free to download, with no in-app purchases.
Which has better reviews, a or Syntactic?
Syntactic is rated higher. a averages 4.6 out of 5 from 553 ratings, while Syntactic averages 5.0 from 1 ratings.
Do a or Syntactic have ads?
Neither a nor Syntactic shows ads.

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