Master algorithms.
Think. Visualize. Conquer.
AlgoKing shows you exactly how each algorithm works — one step at a time — then hands you the controls. You make every decision yourself, and when you get one wrong, it explains why before you move on.
Two steps to really understand an algorithm
Every lesson has the same shape, so once you know one you know them all.
Watch
Step through the algorithm at your own pace. Every step says what happened and why — with the numbers written out, not hidden.
Try
Now you run it, on new data. Tap the next node, pick the right number, choose take or skip — the algorithm only moves when you decide.
Learn from mistakes
A wrong answer never counts against you. You get a nudge, then the exact reason, then the full explanation — never a dead end.
See the working, not just the answer
36 lessons, from first search to shortest paths
17 lessons are free, forever. AlgoKing Pro unlocks the other 19.
Searching
- Linear Search FREE
- Binary Search FREE
Math
- Sieve of Eratosthenes FREE
- Euclid's GCD FREE
Sorting
- Bubble Sort FREE
- Selection Sort FREE
- Insertion Sort FREE
- Merge Sort FREE
- Quick Sort FREE
- Counting Sort FREE
Structures
- Stack FREE
- Queue FREE
- Linked List FREE
- Hash Map FREE
Cryptography
- Caesar Cipher FREE
- XOR Cipher FREE
- SHA-256 Hashing FREE
- AES PRO
- RSA PRO
Advanced
- Two Pointers PRO
- Prefix Sum PRO
- Graph DFS PRO
- Graph BFS PRO
- Dijkstra PRO
- Prim's Algorithm PRO
- Kruskal's Algorithm PRO
- Floyd–Warshall PRO
- Bellman–Ford PRO
- Topological Sort PRO
- Binary Search Tree PRO
- AVL Tree PRO
- Tree Traversal — Inorder PRO
- Tree Traversal — Preorder PRO
- Tree Traversal — Postorder PRO
- Fibonacci (Dynamic Programming) PRO
- 0/1 Knapsack PRO
Go further with Pro
- Unlock all 19 Pro lessons — graphs, trees, dynamic programming, AES and RSA
- No ads, anywhere in the app
- Every free lesson stays free, whether you subscribe or not
Subscribe in the app
Pro is a Google Play subscription. The current price is shown in the app and on Google Play before you buy.
Manage or cancel any time in Google Play → Payments & subscriptions. Already subscribed on another device? Use Restore purchases on the Pro screen.
Simple, and honest about it
Your data
- No account, no sign-in, no email address asked for.
- Your progress is stored on your device (and in Android's own backup, if you have it turned on).
- Lessons run entirely on your phone and work offline.
- Purchases are handled by Google Play — AlgoKing never sees your payment details.
Ads
- Free users may see one full-screen ad after finishing a lesson's practice — when you tap Go to Home. Never during a lesson.
- No banner ads and no rewarded ads — nothing is ever locked behind watching one.
- Ads are served by Google AdMob. Where the law requires it, you are asked for consent first, and can change your choice in Settings.
- AlgoKing Pro removes ads completely.
Questions
Is AlgoKing free?
Yes. 17 lessons — searching, sorting, data structures, the basic ciphers and two math lessons — are free forever. AlgoKing Pro unlocks the other 19.
Who is it for?
Students, self-taught programmers and anyone preparing for coding interviews. No prior knowledge is assumed — each lesson starts from what the algorithm is for.
Do I need an internet connection?
No. Lessons run on your device. A connection is only used for ads (free users) and for Google Play purchases.
Are my answers graded?
No. Practice is never scored. A wrong answer just leads to an explanation, so you can be wrong as often as you like while you learn.
How do I cancel Pro?
Open Google Play → your profile → Payments & subscriptions → Subscriptions, choose AlgoKing and cancel. You keep Pro until the end of the period you paid for.
How do I contact you?
Email irislabs46@gmail.com — questions, bug reports and lesson ideas are all welcome.