Abacus Practice vs Locked In

Practice addition with a clean, distraction-free interface designed to help you focus. Whether you're a student brushing up on math or just want to stay sharp, this app makes it easy. Simple and intuitive design • Completely free - no ads, no sign-ups • Immediate feedback with clear answers • Works great on all screen sizes Perfect for kids, students, or anyone looking to improve their basic math skills in a straightforward, simple app.

Locked In! CISSP is an independent study companion organized around the ISC2 Certified Information Systems Security Professional (CISSP) exam outline effective April 15, 2024. It is built for working security professionals who study in short sessions, and every lesson ends with a quick check. WHAT'S INSIDE • 55 short lessons across all 8 CISSP domains, with every objective in the April 2024 outline mapped to a topic • Diagrams for key concepts: security models, the OSI model, cryptography, IAM, network zones, incident management and more • A quick check at the end of every lesson • 383 multiple-choice practice questions, organized by domain and difficulty, each with an explanation • A 50-question, 75-minute timed practice set with flag-for-review and a final review screen; it does not reproduce the adaptive CISSP CAT or its full item-type mix • 138 flashcards with SM-2 spaced repetition • A free glossary of 106 terms that spells out each acronym with a one-line definition • 15 tap-driven PBQ-style activities written for this app; they are not ISC2 items or an exam simulation • Progress tracking, streaks, bookmarks and personal notes • Spaced review that brings back the questions you missed FREE TO START Free: 12 lessons, a 16-question sampler, 17 Domain 1 flashcards, 2 PBQ-style activities and the full glossary. A one-time purchase unlocks the rest. EXAM UPDATE ISC2 has announced a new CISSP exam outline effective April 15, 2027. This version follows the outline in force since April 15, 2024. WHO IT'S FOR • Security analysts and engineers preparing for the CISSP alongside a day job • IT pros moving into security management and governance roles • Career changers working toward a senior security credential • Anyone who learns better in short, focused sessions than in long lectures WHY LOCKED IN • Bundled lessons and practice work offline, with no account, tracking or ads. Loading, buying and restoring the App Store purchase need a network connection. • One-time unlock, no subscription • Built and maintained by an independent developer • Domain names and weights checked against the ISC2 exam outline on isc2.org in October 2026 PRIVACY Locked In stores your progress on-device. No analytics, no third-party SDKs, no data sold or shared. --- DISCLAIMER Not affiliated with, endorsed by, or sponsored by ISC2. ISC2® and CISSP® are registered marks of ISC2, Inc. Locked In is an independent study aid.