Who is Md. Shahin Akhtar Rupom?

Md. Shahin Akhtar Rupom (often known as Rupom Chowdhury) is a Software Engineer, Microsoft Student Ambassador, and Web Developer at Tech To Cloud (Melbourne, Australia · Remote), specializing in Next.js, Java, Spring Boot, AWS, Azure, and Flutter.

What does Rupom do at Tech To Cloud?

At Tech To Cloud, Rupom works as a full-time Web Developer focusing on Next.js enterprise web applications, AWS cloud infrastructure orchestration, and cross-platform mobile development with Flutter.

What is Rupom's core technology stack?

Rupom's primary stack spans Next.js 15, React 19, TypeScript, Java, Spring Boot, AWS, Azure, Docker, Kubernetes, PostgreSQL, and Flutter for cross-platform apps.

What mobile applications has Rupom developed and published?

Rupom engineered and published PDF Pilot: Smart PDF Tools on the Google Play Store (dev.rupom.pdfpilot). Built with Flutter and Dart, it is a privacy-first, 100% offline Android document utility designed to merge, split, compress, and convert PDFs directly on-device with zero cloud dependencies.

What browser extensions has Rupom developed?

Rupom created Element Hider Pro (extension.rupom.dev/element-hider-pro) for content control across Chrome, Firefox, and Edge, as well as Text Splitter & Counter (extension.rupom.dev/textsplitter) which integrates directly into Chrome's Side Panel for local multi-mode text segmentation, metric counting, and batch exports.

Is Rupom available for freelance, consulting, or speaking engagements?

Yes, Rupom is open to technical advisory, open-source collaboration, workshop speaking on cloud/AI, and select consulting opportunities. Contact him at mail@rupom.dev.

Back to Projects

Mobile & AppsMay 30, 2026Published on Google Play Store

PDF Pilot: Smart PDF Tools

High-Performance Offline Android Document Utility Built with Flutter

Get on Google Play Discuss this Project

PlatformAndroid (API 26+)

Privacy Level100% Offline (Zero Cloud)

ProcessingOn-Device Native Streams

Package IDdev.rupom.pdfpilot

OVERVIEW & PHILOSOPHY

System Architecture Overview

PDF Pilot is a native Android utility engineered to provide fast, professional document manipulation entirely on-device. Designed with strict privacy, zero cloud dependencies, and instant responsiveness, it handles multi-page document operations without sending sensitive data over the internet.

THE ENGINEERING MOTIVATION

Problem Statement

Most mobile PDF tools force user files through remote third-party cloud servers. This introduces bandwidth overhead, latency, subscription paywalls, and critical data privacy risks for users handling bank statements, identification records, or confidential contracts.

SYSTEM ARCHITECTURE

Architectural Blueprint

Deterministic Local File Streams

Processes document buffers in chunked streams directly on the device filesystem, bypassing network transmission completely and enabling instant operations even in airplane mode.

Memory-Efficient Image Pipeline

Converts multi-page documents to compressed images and vice versa using bounded memory pools, preventing out-of-memory errors on mid-range Android devices.

Scoped Storage Compliance

Integrates with modern Android 11+ Scoped Storage APIs to securely read and write output documents without requesting broad storage permissions.

CORE CAPABILITIES

Engineered Feature Toolkit

Multi-File PDF Merging

Combine multiple independent PDF files into a single unified document with preserved bookmarks and vector quality.

Precision Page Splitting & Extraction

Extract individual pages or slice documents by range into standalone PDF files.

Two-Way Image Conversion

Convert photos and gallery images to clean multi-page PDFs, or render PDF pages into high-resolution JPG/PNG images.

Lossless & Lossy Compression

Optimize embedded images and stream tables to significantly reduce file size for email and portal uploads.

Page Reordering & Layout Customization

Interactive visual grid allowing users to drag and drop pages to rearrange layout before saving.

TECHNICAL DEEP DIVE

Engineering Challenges & Solutions

Challenge 01

Handling large 100+ page PDF documents without Android OutOfMemory (OOM) crashes.

Engineering Solution

Implemented lazy page evaluation and stream-based byte buffering. Instead of loading the entire document into RAM at once, PDF Pilot processes pages sequentially through native memory-mapped files.

Challenge 02

Maintaining consistent rendering speeds across varied Android chipsets.

Engineering Solution

Delegated rendering operations to background compute isolates in Dart, ensuring the UI main thread stays locked at 60 to 120 FPS during heavy compression and split workloads.

TECHNOLOGY FOUNDATION

Technology Stack Breakdown

Framework & Language

Flutter 3.xDartAndroid SDK

Document Processing

PDF EngineChunked File StreamsBinary Manipulations

Architecture & Storage

Offline-First PatternScoped StorageLocal Cache Management

OUTCOMES

Measurable Production Impact

Published production app verified and distributed through the Google Play Store.
100% offline architecture eliminates all cloud server costs and data transmission liabilities.
Empowers users to process sensitive legal and financial documents without external privacy risks.