# Start C Programming — See C and memory, line by line

> See C and memory, line by line (iPhone/iPad app by CHUNGKIL KIM.)

- Source: https://appshunter.io/ios/app/start-c-programming/id6819278113 (this page in markdown: same URL + `.md`)
- Developer: [CHUNGKIL KIM](https://appshunter.io/developer/960187999)
- Category: Education
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 18.0 · 49 MB
- Languages: American English, Korean
- Released: 2026-10-11
- Data updated: 2026-11-08

## What is Start C Programming?

Learn C by running code one line at a time and watching memory change.

Pointers are hard because you cannot see them. Each time you run a line, this app draws the stack frame of each call,
the variables inside it, the heap blocks you borrow with malloc, and where each pointer points.
The last changed value turns yellow, and you can step back to see it again.

Step through and rewind

- Run to the next line, a breakpoint, or the end, or step back a line
- Watch frames pile up when a function is called and disappear when it returns
- Pointers are arrows, arrays are rows of slots, and structs show their members and padding
- Tap a variable to see its bytes in hex, decimal, binary, or characters
- Set scanf input, arguments, and files before you run, and see what your program read and wrote
- Write your own headers and link several .c files, as in real C
- Processes and threads appear in tables, with each process's memory, pipes, and sockets drawn
- A virtual microcontroller board shows its LEDs, buttons, registers, and terminal

10 tracks and two appendices, 447 lessons

- Track 0 First steps in programming — hardware, operating systems, bits and files, algorithms, and bugs (20 lessons)
- Track 1 Programming basics — values, conditions, loops, and functions (16 lessons)
- Track 2 The C language — printf to pointers, structs, dynamic memory, file I/O, and function pointers (68 lessons)
- Track 3 Memory essentials — bits and bytes, the memory map, the stack and the heap, and memory bugs (33 lessons)
- Track 4 Executable essentials — compiling and linking, assembly, object files, and executable formats (36 lessons)
- Track 5 Capstone projects — a string processor, a linked list, a memory allocator, an RPN calculator, and a word counter (27 lessons)
- Track 6 Systems programming — fork, pipes, threads, shared memory, sockets, and poll, then a work queue and a chat room (51 lessons)
- Track 7 C for embedded development — registers, GPIO, timers and PWM, interrupts, UART, and flash and RAM on a virtual board (42 lessons)
- Track 8 Data structures in C — growing arrays, generic containers, hash tables, balanced trees, tries, and graphs, then an LRU cache (33 lessons)
- Track 9 Building a language in C — what C promises, undefined behavior, closures and exceptions in C, garbage collection, and a bytecode VM (35 lessons)
- Appendix A Computing and the lineage of C — computing history up to C and what C89 to C23 changed (51 lessons)
- Appendix B Computer science beyond C — algorithms, the CPU, the OS, networks, and the limits of computation (35 lessons)

Lessons are short cards with examples you run in place, marked beginner, intermediate, or advanced.
Each module has a quiz, track modules have auto-graded exercises with hints, and each track ends with a final quiz.
A placement quiz suggests where to start, with Track 0 for new programmers.

Errors explained

- Errors and warnings are caught where clang catches them, with an explanation, a fix, and a related lesson
- Out-of-bounds writes, use after free, double frees, and leaks stop or warn where they happen, with what real C would do
- Data races, deadlocks, and phone typos like curly quotes are flagged too

Like real C

- Supports C99 and C11
- Hundreds of test programs match clang on a Mac, down to the exit status
- Files live in a virtual file system inside the app
- Processes, sockets, and the virtual board run inside the app; networking is loopback only, and no real hardware is touched

On your device, with no internet

A C interpreter built into the app runs everything on your device. Progress syncs through your own iCloud.
There are no ads.

Start for free

All of Tracks 0 and 1, the first module of Tracks 2 to 9, and both appendices are free. The other modules open with a one-time purchase per track,
which also opens modules added in later updates. One purchase works on both iPhone and iPad.

On iPad, code, memory, and output sit side by side, and you can open several windows.

## Pricing and in-app purchases

Base price: Free.

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Track 8: Data structures in C | $5.99 | one-time |
| Track 9: Building a language | $5.99 | one-time |
| Track 3: Memory essentials | $5.99 | one-time |
| Track 4: Executable essentials | $5.99 | one-time |
| Track 2: The C language | $5.99 | one-time |
| Track 5: Capstone projects | $5.99 | one-time |
| Track 6: Systems programming | $7.99 | one-time |
| Track 7: Embedded C | $7.99 | one-time |


## Is Start C Programming safe?

Not enough ratings yet to assess Start C Programming.

## Is Start C Programming legit?

Start C Programming appears legitimate, with a few gaps. The AppsHunter Legitimacy Score for Start C Programming is 75 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 5 releases)

### 1.9.0 — 2026-11-07

1.9.0 업데이트

- 연습장에서 내 헤더 파일을 만들어 #include "point.h"로 넣을 수 있습니다. 파일 칸에서 헤더를 더하면 에디터 위에 main.c와 헤더의 탭이 생겨 같은 에디터로 고치고, 헤더 안의 줄에도 중단점을 걸어 한 줄씩 실행합니다. 오류와 경고는 clang처럼 헤더의 파일과 줄, "In file included from"으로 알려 줍니다.
- 연습장 파일 칸의 .c 파일을 main.c와 함께 이어 실행합니다(cc main.c util.c처럼). 다른 파일의 함수로 들어가면 코드 칸이 그 파일을 보여 주고, 같은 이름을 두 파일에서 정의하거나 정의가 없으면 링커처럼 알려 줍니다.
- iPad에서 창을 여러 개 띄울 수 있습니다. 레슨·실습·연습장 코드를 꾹 눌러 "새 창에서 열기"로 나란히 놓고, 창마다 보던 화면을 기억합니다. 같은 연습장 코드는 한 창에서만 고칩니다.
- iPad 메뉴 막대에 "실행" 메뉴가 생겨 단계 실행과 채점의 키보드 단축키를 볼 수 있습니다.

불편한 점은 지원 페이지로 알려 주세요.

### 1.8.0 — 2026-11-05

What's new in 1.8.0

- New Track 8 "Data structures in C". Build a growing array, store any element type with void * and comparison functions, write a hash table that handles deletion and rehashing, balance a tree with rotations, build a trie, and work through graph algorithms (depth-first search, topological sort, Dijkstra, and union-find), then combine a hash table and a doubly linked list into an LRU cache. 7 modules, 33 lessons, and 14 exercises. The first module, 8.1 "Growing arrays", is free, and the rest open with the Track 8 purchase.
- New Track 9 "Building a language in C". See what the C standard promises and how undefined behavior shows up under optimization, then imitate closures, virtual function tables, exceptions, and resumable functions in C. Build reference counting and mark-and-sweep to clean up memory automatically, then make a small language of your own, from a lexer and parser through a symbol table and type checking to a bytecode virtual machine. 7 modules, 35 lessons, and 14 exercises. The first module, 9.1 "What C promises", is free, and the rest open with the Track 9 purchase.
- Memory pictures show realloc moving a block while an old pointer still points to the freed one, the arrows a rotation changes, the environment a closure keeps on the heap, and the nodes of a syntax tree linked on the heap. Assembly shows how clang -O2 on a Mac changes C that has undefined behavior.
- Finishing each track opens a final quiz of 5 basic and 5 advanced questions.
- There are now 447 lessons and 161 exercises.

Tell us about any problem through the support page.

### 1.7.0 — 2026-10-30

What's new in 1.7.0

- Appendix B "Computer science beyond C" (free, 35 lessons): the speed of algorithms and data structures, inside the CPU, the operating system, and the network, the limits of numbers and computation, and how this app's interpreter runs your C, with pictures and examples. It has module quizzes, a final quiz, and exercises in the algorithm and data structure modules.
- Today's Review: questions you missed in quizzes and lesson check cards come back from the next day. Answer up to 10 at a time from "Today's Review" on Home; questions you get right return less often, after 1, 3, 7, 14, and 30 days, and ones you miss come back the next day. Questions you missed before this update are included.
- iCloud sync: lesson progress, quiz answers and scores, and exercise grades carry over between iPhone and iPad signed in to iCloud with the same Apple Account. There is nothing to sign up for, and if you turn this app off under iCloud in iOS Settings, that device keeps its records to itself.
- Reset progress in Settings now also erases your records on your other devices that use the same iCloud account (playground code stays).
- Run limits: in Settings › Run Limits you can set the number of instructions, the time, and the stack, heap, and global sizes. Long-running programs and deep recursion can now run, and the limits apply to lesson examples, stepping, and exercise grading. Running a lesson card and grading an exercise now have a Stop button.
- Playground: the code you write in the playground is now saved automatically as you edit. Keep several programs in the playground list, rename or delete them, and they keep their input, command-line arguments, and files, carrying over to your other devices through iCloud.
- Lesson search: type a word such as malloc or pointer in the search field at the top of the Course tab to find lessons by title, text, and the code on their cards.
- Fixed memset and memcpy handling only the first part of memory blocks larger than 1MB.

Tell us about any problem through the support page.

### 1.6.0 — 2026-10-29

What's new in 1.6.0

- New module 7.8 in Track 7, "Timers and PWM": the virtual board now has a general-purpose timer, TIM2. In 5 lessons, a quiz, and 3 exercises, you measure time with the prescaler and auto-reload, take update interrupts, and set LED brightness with PWM.
- Board panel: an LED driven by PWM is drawn at its brightness over one period, with a label like "25%" under its number. Using TIM2 shows a TIM2 register table, and using alternate functions adds AFRL and AFRH rows.
- Exercises about LED brightness also check that the LED is lit at the right brightness at the end.
- Track 7 now has 42 lessons, so its final quiz opens again once you finish the new module 7.8. Scores you already have stay.

Tell us about any problem through the support page.

### 1.5.0 — 2026-10-27

What's new in 1.5.0

- New free Track 0, "First steps in programming": before you write code, 20 lessons cover programs and operating systems, bits and files, algorithms, programming languages, and bugs and debugging. Read a question, think for a moment, then tap "Show answer."
- A final quiz for every track: finish a track's lessons to open a final quiz of 5 basic and 5 advanced questions, and jump from a missed question to its lesson. Track headers show your lesson progress and final quiz score.
- If programming is new to you, the app now suggests starting with Track 0.
- Track 6 sockets: a connect interrupted by a signal now times out as it does on macOS, and the error it leaves can be read with SO_ERROR or the next recv.

Tell us about any problem through the support page.

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All apps by CHUNGKIL KIM: https://appshunter.io/developer/960187999

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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 2026-11-08.*