# CodeSequence

> CodeSequence (iPhone/iPad app by Alfonso Sanchez.)

- Source: https://appshunter.io/ios/app/codesequence/id6816369564 (this page in markdown: same URL + `.md`)
- Developer: [Alfonso Sanchez](https://appshunter.io/developer/1895465364)
- Category: Education, Developer Tools
- Price: Free
- Age rating: 4+
- Requires: iOS 17.0 · 8 MB
- Languages: American English
- Released: 2026-10-08
- Data updated: 2026-10-10
- User reviews in markdown: https://appshunter.io/ios/app/codesequence/id6816369564/reviews.md

## What is CodeSequence?

CodeSequence teaches data structures and algorithms along a clear path: first you understand the idea, then you watch it work step by step, recall it without looking and, finally, apply it to real problems.

A PATH IN THE RIGHT ORDER
- 12 chapters and 35 topics ordered by dependency, from complexity analysis and arrays to graphs and dynamic programming.
- Every lesson in four steps: Understand, Visualize, Retrieve and Connect.
- The app always shows you your next lesson.

WATCH IT WORK
- Interactive animations for arrays, linked lists, stacks, queues, trees, heaps, graphs and sorting algorithms.
- Move step by step, adjust the speed and follow every pointer, index and decision.
- Diagrams, Big-O complexity tables and common mistakes for every topic.

REMEMBER IT FOR REAL
- Quick questions in every lesson, with an explanation for each answer.
- Code exercises: fill in snippets and match concepts.
- Spaced-review cards that come back right as you start to forget them, with optional reminders.

PRACTICE WITHOUT SPOILERS
- 102 interview problems, with a broad set of easy problems to get started.
- Progressive hints that unlock in order, and solutions you only see after you've tried.
- Reasoned solutions, from brute force to optimal, in Swift, Python, Java and JavaScript.
- An editor to write your solution and run it.
- Interview mode: a random problem against a 45-minute clock.

A PLAN FOR EVERY DAY
- The Today screen suggests three short steps: learn, review and apply.
- Streak, recent activity and mastery by topic, just for you.

BUILT FOR STUDYING
- In English and Spanish; switch language whenever you like.
- Light and dark mode, and text that adapts to the size you use on your iPhone or iPad.
- For iPhone and iPad.

Your progress stays on your device. No accounts, no ads and no leaderboards. Your code is only sent to an execution service when you tap Run.


## Version history (last 1 release)

### 1.0 — 2026-10-08

No release notes.

## More apps by Alfonso Sanchez

- [Creatine Journey](https://appshunter.io/ios/app/creatine-journey/id6763736198)
- [Study AWS Developer Associate](https://appshunter.io/ios/app/study-aws-developer-associate/id6777165133)
- [NFC Play!](https://appshunter.io/ios/app/nfc-play/id6777405956)
- [Padellers](https://appshunter.io/ios/app/padellers/id6779987354)
- [Game Inventory](https://appshunter.io/ios/app/game-inventory/id6816246969)

All apps by Alfonso Sanchez: https://appshunter.io/developer/1895465364

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-10-10.*