a vs Cron Lab

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.

Cron Lab reads and writes cron schedule expressions. Type one like "*/15 9-17 * * 1-5" and it tells you, in plain English, what it means, when it will run next in your timezone, and what might quietly break it. Cron Lab is free. Four features (Convert, In words, backup and restore, and the Home Screen widget) are part of Cron Lab Pro, a one-time $0.99 in-app purchase. Everything else listed below is free, and there is no subscription. FREE • Plain-English translation. Every expression becomes a clear sentence as you type, with a field-by-field breakdown below it. • Next runs. Accurate, DST-safe previews for any IANA timezone, in 12- or 24-hour time. • Visual builder. Tap together a valid expression: every N minutes, specific days, ranges, steps, and lists. • Schedule doctor. Explains why an expression never runs (February has no 30th), warns about leap-year-only dates, and flags the day-of-month / day-of-week OR rule that surprises almost everyone. • Examples and reference. A categorized library of common schedules and a built-in syntax cheat sheet. • Your library. Save and label expressions, and browse recent history. CRON LAB PRO (a one-time $0.99 in-app purchase) • Convert. Turn a standard crontab line into Quartz, Spring @Scheduled, AWS EventBridge, Jenkins, Kubernetes CronJob, or GitHub Actions. Handles the tricky parts (seconds, day-of-week numbering, the "?" rule) and includes copy-ready snippets, like the full CronJob YAML. • In words. Type "every weekday at 9am" or "the 1st of the month at noon" and get the matching expression. • Backup and restore. Save your whole library to a JSON file and load it back. • Home Screen widget. Pin a schedule to see its meaning and next run without opening the app. PRIVATE BY DESIGN • No ads, no tracking, no account. Your schedules never leave your device. • Works completely offline. • Clean, minimal design with full light and dark mode. • VoiceOver labels, legible contrast, large tap targets. • Supports 5-field crontab and 6-field (seconds) expressions, names (JAN-DEC, SUN-SAT), ranges, steps, lists, and @shortcuts (@daily, @reboot, and more). Cron Lab Pro is a one-time $0.99 in-app purchase, not a subscription.