Frontend Masters vs OpeningBook

Master the most important JavaScript and front-end development skills like React, Node.js, Vue, Functional JavaScript, CSS Grid, Flexbox, and more — with 100+ fresh web development courses on Frontend Masters! This iOS App features: - Save videos to your device! Watch on-the-go, on or offline (on the plane, or a train, or in space) - Access to our entire course catalog and new courses as they’re released. - Never lose where you’ve left off — progress syncs online and offline! Subscription Options: • Unlimited - full access for $39.99 per month or $399.99 per year. Cancel anytime. Payment will be charged to iTunes Account at confirmation of purchase. Subscription automatically renews unless auto-renew is turned off at least 24-hours before the end of the current period. Account will be charged for renewal within 24-hours prior to the end of the current period at the prices quoted above. Subscriptions may be managed by the user and auto-renewal may be turned off by going to the user's Account Settings after purchase. Any unused portion of a free trial period, if offered, will be forfeited when the user purchases a subscription to that publication, where applicable. Terms of Service: https://frontendmasters.com/company/terms/ Privacy policy: https://frontendmasters.com/company/privacy/ For issues, the iOS issues repo is now public! https://github.com/FrontendMasters/ios-issues For customer support, email us at support@frontendmasters.com

OpeningBook is a clean, offline reference and trainer for chess openings. BROWSE EVERYTHING • Thousands of named openings and variations, organized by ECO volume (A–E), family, and line — sourced from the open Lichess openings database. • Step through any line move-by-move on a real, playable board. • Read key ideas and classic traps for the major openings. SEARCH & FILTER • Find any opening by name, ECO code, or move sequence. • Filter by line length with a simple move-count slider. TRAIN YOUR REPERTOIRE • Add lines to your training set as White or Black. • Drill them in a play-your-side-vs-app loop. • Spaced repetition brings each line back for review at the right time. 100% offline. No account, no ads, no tracking.