iCoder - Advanced Algorithms

8th anniversary: 1000+ offline LeetCode problems, zero ads, daily quizzes, widgets, bilingual UI, fresh SwiftUI for iOS 16+. Eight years of focus. Prep smarter today.

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.