Every product on this page was designed, engineered, and deployed by Kalenux. From high-traffic editorial platforms to privacy-focused browser tools, from multilingual cognitive assessment systems to encrypted mobile security apps - these are real products with real users, built from scratch without shortcuts.
Production web platforms serving real audiences, built on robust backend infrastructure and deployed continuously.
When Notes Fly is a high-traffic editorial magazine dedicated to the life of the mind - covering thinking, learning, technology, culture, and the skills that define modern professional life. Every article is written to go deeper than a typical blog post, combining research-backed analysis with accessible prose that a curious generalist can follow. The platform organises its content into six primary topic areas - Concepts, Culture, Explainers, Ideas, Technology, and Work Skills - each subdivided into ten focused subtopics, giving readers a structured but exploratory way to navigate a large and growing library of pieces. Behind the scenes, the platform is built on a full Go/Gin REST API server, a PostgreSQL 15 database, Redis caching for performance at scale, and Docker-based deployment coordinated by Nginx as the reverse proxy.
The architecture follows a clean separation between the API layer and the frontend. The Go backend exposes authenticated endpoints for content creation and management, handles subscriber verification, drives the practice engine that powers the site's IQ and cognitive assessment modules, and manages a cookie consent system compliant with privacy regulations. The Kalenuxer build system compiles the frontend into optimised, minified static assets that are then served through Nginx, keeping page loads fast even on slower connections. The admin dashboard gives editors full control over articles, categories, scheduling, and subscriber management without touching the codebase.
When Notes Fly is built for readers who want more than surface-level takes - people who read to think, not just to stay informed. It is also the flagship product that stress-tests every Kalenux technology decision, from the build pipeline to the deployment workflow, making it the reference implementation for every other Kalenux web project.
Whats Your IQ is a multilingual cognitive assessment platform that goes well beyond the single-score IQ tests that populate most of the web. The platform structures its question banks around five distinct cognitive domains - verbal reasoning, spatial reasoning, numerical ability, logical deduction, and pattern recognition - and reports a separate domain score for each, giving users a meaningful profile of their cognitive strengths rather than a single number with no interpretive context. Tests are delivered with full randomisation at both the question and answer-option level, so no two sessions are identical and score inflation through memorisation is prevented by design.
The platform is built entirely with JavaScript and the Kalenuxer build system, with no server-side processing required during a test session. Question banks are loaded in structured JSON files that map cleanly to the multilingual data architecture Kalenuxer uses across all Kalenux web projects. Results analytics are computed client-side and persisted in browser storage, allowing progress tracking across multiple sessions without any account requirement. The scoring algorithm accounts for randomisation order and applies domain-specific weighting to produce results that are consistent regardless of which question subset a user encounters.
The platform serves users across many language regions, with full localisation of all UI text, instructions, and result descriptions. It is aimed at students, professionals, and anyone curious about their own cognitive profile - a broad audience that benefits most from a clean, fast, no-barrier experience that works on any device without installation.
File Converter Free is a browser-based file conversion platform built on a single, non-negotiable principle: your files never leave your device. Every conversion operation - whether you are converting a Word document to PDF, reformatting an image from PNG to WebP, or changing an audio file from MP3 to OGG - runs entirely inside the browser using JavaScript and WebAssembly. There is no server receiving your data, no upload progress bar, and no third-party service handling sensitive documents. The file goes in, the converted file comes out, and nothing in between touches a network connection.
This architecture is made possible by compiling format conversion libraries to WebAssembly, allowing code that would traditionally run on a server to execute at near-native speed inside the browser sandbox. The platform uses the browser's File API to read input files directly from disk, processes them through the appropriate WebAssembly module, and writes the output back through a generated download link. Because processing happens on the user's own hardware, conversion speed scales with the user's device rather than with server load - a fast local machine converts faster, and there is never a queue to wait in.
The platform is designed for anyone who has ever felt uncomfortable uploading a confidential document to an online converter - legal professionals, medical staff, journalists, or simply privacy-conscious individuals who do not want their files on a stranger's server. No sign-up, no subscription, no file size limit imposed by server costs. Just open the page and convert.
QR & Barcode Tool is a comprehensive web platform for generating and scanning QR codes and barcodes of all common formats, built as a Progressive Web App so it installs on any device and works fully offline. The generator side supports every practical QR code data type - URL, plain text, contact card (vCard), WiFi network credentials, email address, phone number, and SMS - and produces output in PNG, SVG, and PDF formats so the result is useful whether it ends up on a website, a business card, or a printed flyer. Custom colours, logo embedding, and error correction level selection give designers the control they need for branded code generation.
The scanner side uses the device camera through the WebRTC API and runs a real-time decode pipeline that recognises QR codes, Code 128, Code 39, EAN-13, EAN-8, UPC-A, UPC-E, and Data Matrix formats without requiring any app installation. Scan results are logged to a local history with timestamps and the raw decoded payload, making it practical as a professional scanning tool for inventory, logistics, or event check-in workflows. The batch generation feature allows creating multiple codes from a CSV upload in a single pass, with bulk download as a ZIP archive.
Because the platform is a PWA, it adds to the home screen on Android and iOS, behaves like a native app with a full-screen interface, and caches all assets for reliable offline operation. This makes it equally useful in warehouse environments with poor connectivity, at outdoor events, or anywhere a browser-based tool needs native-app reliability.
Published Android applications built natively with Java and Kotlin. Each app solves a specific problem that mainstream apps handle poorly - too many permissions, too much cloud dependence, too little respect for the user's privacy and storage.
A fully offline reading and editing application that treats both PDF and EPUB as first-class formats rather than bolting one on as an afterthought. The app opens large documents quickly with progressive page rendering, so you are reading within seconds rather than waiting for the whole file to load into memory. Annotations, highlights, and bookmarks are stored locally alongside the document and survive app restarts without requiring any cloud account. Three built-in reading themes - white, sepia, and night - cover every lighting environment, and adjustable font size and family settings make the reading experience genuinely comfortable for extended sessions. The text-to-speech integration reads any document aloud with sentence-level highlighting so you can follow along, turning commute time into reading time. For EPUB files, the table of contents panel gives instant chapter-level navigation, and the in-document search locates specific passages across the entire book in under a second.
A multi-format scanner with a built-in generator that opens directly to the camera viewfinder with no splash screen delay. The real-time scan engine uses the device camera to automatically detect and decode QR codes, Code 128, EAN-13, EAN-8, UPC-A, and UPC-E barcodes without requiring the user to select a format manually. Every successful scan is added to a local history log with a timestamp and the full decoded payload, so you can go back to a scan from days ago without re-scanning anything. Results can be shared directly to any app, opened as a URL, copied to clipboard, or saved as a contact in a single tap. The built-in generator produces QR codes for URLs, contact cards, WiFi network credentials, and plain text, which can be shared as an image or displayed on-screen for another device to scan. The app requests only the camera permission it actually needs and makes no network requests beyond what the user explicitly triggers by opening a scanned URL.
A device diagnostics tool that gives you the information your manufacturer's settings app deliberately withholds. The battery module reads the current charge level, battery health status, estimated charge cycle count, and real-time temperature, presenting the data in a clear timeline so you can see whether your battery is degrading faster than expected. The performance module displays live CPU usage per core, total RAM allocation and free memory, and storage breakdown by category - apps, media, documents, system - so you know exactly what is consuming space before you start deleting things. The sensor health panel tests the gyroscope, accelerometer, and compass by running each through a short calibration routine and reporting whether the readings are within normal range, which is useful when diagnosing motion-related issues in games or navigation apps. A built-in network speed test measures download and upload throughput on both WiFi and mobile data, and a device benchmark runs a standardised compute workload to give a single performance score you can compare across devices or across time on the same device.
A mobile coding assistant built for developers who switch between their desk and their phone and do not want to lose momentum. The core of the app is a snippet library containing over 500 hand-curated code snippets across more than 20 programming languages - JavaScript, TypeScript, Python, Go, Rust, Java, Kotlin, Swift, SQL, Bash, and more - each with a plain-English explanation of what the snippet does and when to use it. Snippets are searchable by keyword, filterable by language, and copy to clipboard in one tap. The documentation browser provides offline syntax reference for the most commonly used standard libraries, so you can look up how a language feature works without burning mobile data on a documentation website. The regex tester lets you write and test regular expressions against sample input with live match highlighting, which is useful when you cannot remember whether a pattern uses a capturing group or a non-capturing one. Additional utilities include a JSON and XML formatter and validator, a base64 encoder and decoder, a URL encoder and decoder, a Unix timestamp converter, and a color picker that outputs hex, RGB, and HSL values for use in CSS or design tools.
An encrypted file security application that uses AES-256 encryption to protect files and folders on the device with no cloud dependency whatsoever. The encryption and decryption operations happen entirely on-device using the Android Keystore system, which means the encryption key never leaves the hardware security module and cannot be extracted even if the device is physically compromised. The app unlocks with a PIN or biometric authentication depending on the device's capabilities, and it supports a hidden vault mode that presents a functional calculator interface to anyone who opens the app without the correct unlock sequence - a useful feature for protecting sensitive content in situations where showing a lock app would itself attract unwanted attention. The secure photo vault imports photos and videos from the gallery, encrypts them, and deletes the originals, so the files no longer appear in any gallery app or backup. Encrypted notes provide a private text store that sits outside the standard notes ecosystem. Import and export of encrypted containers allows moving a vault between devices over a local cable without any file ever being decrypted in transit.
A Node.js build pipeline that replaces the full stack of separate tools - template engine, CSS preprocessor, JS bundler, image optimiser, deployment script - with a single coherent system. Every Kalenux web product is built and deployed with it.
Kalenux designs and builds web platforms, mobile apps, and custom tools to the same standard as every product on this page. Direct communication, no outsourcing, and full ownership of everything delivered.