I'm an active CCNA. While studying I wanted random subnetting questions on my phone — the kind the testing center throws at you — drilled with the magic-number method I learned in class. Couldn't find an app that did exactly that, so I built one.
It's called Slash. Free. No ads, no accounts, no sign-in, no tracking, no network calls. iPhone and iPad.
What it does:
- Random questions: find the network, broadcast, first usable host, last usable host
- Mixed text input and multiple choice
- Wrong answer → walks the magic-number method step by step, plus a "Quick Way" shortcut tailored to that question
- Right Neighborhood detection: if you typed the network when asked for the first host, it tells you you got the math right and only got the wrong field — so the next time, you fix the mistake, not the math
- Cheat sheet one tap away from any question — the same magic-box grid you'd scribble at the start of the exam
- Progress tracking with a "You're Ready" badge once you've cleared 50 answers at 90% accuracy with cross-octet and /30 questions in the bag
The method isn't original — it's the magic-number / block-size approach a CCNA instructor taught me, with my own take on how to lay out the worked example. The app's job is to be the pencil-and-paper part of exam prep without needing the pencil or paper (except to practice).
App Store: https://apps.apple.com/app/id6764183064
If something feels off, tell me — I'm the only one working on it.