iCoder vs Quarry

Eight years. One mission: help you master algorithms without distractions. iCoder is a LeetCode practice app trusted since day one by learners preparing for technical interviews. Version 8.0 marks our 8th anniversary with a complete SwiftUI rebuild: faster, cleaner, and ready for iOS 16 and later. Still 1000+ classic problems, still offline, still no ad popups. WHY iCODER - Born for interview prep: company-tagged problems mirror what top firms often ask - Organized by difficulty, tags, and companies so you can drill weak spots - Offline-first: the library lives on your device; browse, quiz, and widgets work without Wi-Fi - Eight years of polish: now with a modern SwiftUI interface and rich widgets BROWSE AND SEARCH - Numbered list or compact grid with adjustable columns on iPhone and iPad - Filter by Easy, Medium, Hard, VIP, favorites, and learning status - Optional Favorites and Recently Viewed at the top of the Problems tab - Search by problem ID, title, content, tag, or company - Swipe and context menus for favorites and status CATEGORIES - Algorithm tags from arrays to dynamic programming - Company collections for targeted interview practice - Smooth flow from filters to detail PROBLEM DETAIL - Bilingual Chinese and English descriptions - Adjustable font size - Unlearned, Learned, and Mastered tracking - Toolbar favorites and solution links when online - Share a long image for notes or study groups - Previous and next problem navigation DAILY QUIZ AND REVIEW - Ten questions per day by difficulty, tag, or company - Today score, best score, and streak - Wrong Book with one-tap return to full problem detail - Reshuffle for extra practice the same day LEARNING TRACKING - Favorites and Recently Viewed lists in Settings - One-tap clear all recents - Stats for favorites, learned rate, and mastered rate WIDGETS (iOS 16 AND LATER) - Daily Problem, Difficulty Glance, Daily Quiz, Favorites, Wrong Book, Learning Progress, Company Spotlight - Lock Screen and StandBy compact layouts; deep-link into the app - On iOS 17 and later: shuffle from Daily Problem and Company Spotlight Home Screen widgets without opening the app - In-app Widget Guide with FAQ PERSONALIZATION - Sixteen accent colors; Light, Dark, or System - Widget backgrounds can match your theme - English, Simplified Chinese, Traditional Chinese, or Follow System - List or grid layout with custom column count SHORTCUTS - Up to four Home Screen quick actions on long-press - Deep links from widgets and shortcuts - iPad and Mac keyboard shortcuts SUPPORT - Rate, email feedback, share the app, tip the developer - More apps from the developer - Optional App Store update reminder OUR PROMISE SINCE YEAR ONE - No ad popups inside the app - Offline problem library - Your time is precious; we respect it Requires iOS 16.0 or later. Download iCoder 8.0 and celebrate eight years of practice with us.

Quarry is a focused, offline gym for data and coding interviews. 108 hand-picked problems across SQL, pandas, and Python — write real code, run it on your device, and get graded instantly. Everything runs on-device. The SQL and Python engines are built into the app, so there's no sign-up, no internet requirement, and nothing you write ever leaves your phone or iPad. Practice on a plane, on the subway, or anywhere. WHAT'S INSIDE • 108 problems across three tracks: SQL queries, pandas data wrangling, and Python algorithms & data structures. • Real execution, real grading. Your output is checked against the expected result — no self-marking. • Company tags. Filter problems by the company you're interviewing at. • Hints and full solutions when you're stuck. • Difficulty levels from Easy to Hard, grouped by topic. • A free-form Playground for scratch SQL and Python. • Universal app — designed for both iPhone and iPad. PRIVATE BY DESIGN No accounts. No analytics. No ads. No tracking. Quarry collects nothing and works fully offline. Whether you're prepping for a data analyst, data engineer, data scientist, or software role, Quarry gives you a quiet, fast place to actually practice.