Chmod Toolkit
Learn Unix permissions with explanations, practice questions and certification-style exams.
Robert Frederique · Utilities · Free
iPhone screenshots
How it uses iPhone Duo
Half-folding arranges flashcards on either side of the crease; views retain their place through folding.
What’s New
Version 3.4 ·
Ready for iPhone Duo. • Built for iPhone Duo: every screen lays out for the inner display, in any orientation, and keeps its place through a fold. Fold the phone halfway and Flashcards settle on either side of the crease. • Sharper quiz feedback: get an answer wrong and ChmodIQ shows exactly what your answer would do, bit by bit, next to the right one. • Ready for Linux+ XK0-006: objectives updated for the current exam, plus new questions on symbolic modes, special bits, SELinux and password aging. • Fixes and polish throughout.
App Store descriptionWritten by the developer.
The most comprehensive Unix permissions learning tool available on any platform. Master chmod, chown, umask, ACLs, SELinux, and everything in between, then prove you know it under real exam conditions. Whether you're preparing for a Linux certification exam, hardening production servers, or learning Unix for the first time, Chmod Toolkit gives you the knowledge, the practice, and the proof. SIMULATE REAL CERTIFICATION EXAMS Three cert-specific exam modes that match actual exam methodology. Linux+ simulation: 90 questions, 90-minute timer, scaled scoring to 720/900. LPIC-1: 60 questions with fill-in-the-blank, 90 minutes, scored to 500/800. RHCSA: 18 hands-on tasks, 3 hours, reference materials available, just like the real exam. Skip, flag, and return to any question. Domain-by-domain results tell you exactly where to improve. READY FOR iPHONE DUO Every screen lays out for the inner display, in any orientation, and keeps its place through a fold. Prop the phone open and Flashcards settle on either side of the crease. MASTER PERMISSIONS, NOT JUST MEMORIZE THEM Spaced repetition tracks what you actually know, not what you crammed yesterday. Reviews are scheduled based on your accuracy, spending time where it matters most. Eight question types keep you sharp: multiple choice, type the octal, symbolic conversion, true/false, scenarios, fill-in-the-blank, typed commands, and multi-step task planning. Get an answer wrong and ChmodIQ shows exactly what your answer would do, bit by bit, next to the right one. PREPARE BY EXAM DOMAIN Study by exam domain for CompTIA Linux+ (XK0-006), LPIC-1, and RHCSA. Every question maps to specific exam objectives so you know exactly what you're covering. Domain-by-domain progress tracking tells you when you're ready to test, and where to focus when you're not. SEE YOUR GROWTH A full stats dashboard with interactive charts shows your accuracy trends, category strengths, question type breakdown, difficulty performance, and certification readiness. Triple progress rings, daily challenge streaks, and engagement metrics give you the complete picture. A COMPLETE MASTERY SYSTEM Learn the concepts with structured study topics. Practice with quizzes and daily challenges. Reinforce with flashcards that surface questions you've already attempted. Track your readiness with the stats dashboard. Prove it with exam simulation. Calculate permissions instantly, scan for security issues, and diagnose errors, all on-device. Every feature serves one goal: mastery. BUILT FOR EVERY APPLE DEVICE iPhone with haptic feedback and sound effects. iPad with full-screen layouts and split view. Mac with native sidebar navigation, keyboard shortcuts, and drag-and-drop folder scanning. iCloud syncs your progress across all your devices automatically. One purchase. No subscription. Every future update included. No account required. No data leaves your device. Your progress, your privacy.
Chmod Toolkit on iPhone Duo: FAQ
Is Chmod Toolkit optimized for iPhone Duo?
Yes. Chmod Toolkit is Built for Duo: it uses the fold, Split View or the outer display. Verified on October 28, 2026 (Developer statement).
What does Chmod Toolkit look like on iPhone Duo?
Half-folding arranges flashcards on either side of the crease; views retain their place through folding.
How much does Chmod Toolkit cost?
Chmod Toolkit is free to download on the App Store.
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