Md Tanvir H. Email & Phone Number

Dhaka, Bangladesh

Accomplishments include:• Architected various native and hybrid Android and iOS projects (Swift, Java/Kotlin, and React Native/Flutter)• Developed mobile applications for more than 30 clients from across different countries ensuring product quality and deadline.• Spearheaded the design and implementation of critical functionalities on the middleware side, optimized database structure, and tailored the Android framework to ensure compatibility across diverse devices, leading to a 50% boost in app performance and enhanced user satisfaction.• Analyzed the requirements, and understanding the functional specifications.• Developed applications from specifications and requirement gathering.• Gathered requirements and design for project, maintenance system by gather anddesign new project requirements.• Orchestrated seamless integration of backend API services in coordination with the web services team, optimizing network calling processes and achieving a 50% improvement in response time.Tech Stacks: #Firebase (Database, Storage, Cloud Messaging, etc)#Push Notification #In-App Purchase, PayPal, Stripe SDK#Google APIs i.e. Map, Places, Direction#Google Analytics for tracking#AdMob Integration#Web Services (XML, JSON)#Amazon AWS (Elastic Beanstalk, Mobile Hub, S3, CodeCommit)#Version control system (GitHub, BitBucket, Git)#Agile Methodology (Asana, Trello, Jira, ClickUp)#Android Billing Library

Singapore

Pluang is one of the fastest-growing Fintech startups in Southeast Asia. As a Senior Android Developer in this product-based startup, my role was to lead the growth squad.Accomplishments include: • Implemented innovative design features and optimized user experience resulting in a 20% increase in app engagement and a 15% decrease in user churn rate. • Directed architectural design decisions and fine-tuned end-to-end application functionality; achieved a 40% reduction in system response time, resulting in improved user experience and increased customer satisfaction. • Designed, developed, and maintained Pluang Android application • Developed with cross-functional teams to define, design, and ship new features. • Managed features independtly which resulted in growth of Pluang. • Wrote high-quality, efficient, and maintainable code. • Established modules, scope analysis, design, build, test the code. • Achieved 97% crash-free users from 90% by fixing critical crashes and bugs throughout the application. • Developed individually as well as part of a larger team on developing and maintainingapplication, Reviewing other developers’ code. • Facilitated in deciding Architecture Designs. • Fine tuned the complete Application end to end. • Tested the application on different Android phones, and tablets, debugged on a real device,and debugged the issues that were found. • Achieved pixel-perfect UI and developer & and scaled features that brought growth to the company. • Shared ideas with the team and contribute to global app architecture (MVVM).Tech stack: # Kotlin # Java # MVVM # KMP # KMM # Clean architecture # Coroutines # Dagger2 # RxJava # Android Navigation Component # Figma # Firebase # AppsFlyer # OneSignal # Android NDK # C++ # Proguard # Material UI # Gson # Retrofit # Android Studio # Leadership # Communication

Berlin, Germany

Blloc is a Berlin-based startup. Their core product is Ratio which is an Android Launcher Application. Ratio is known for its minimalist design, using a monochromatic color scheme and a card-based layout. It organizes apps into cards based on categories, and it aims to reduce the time users spend on their phones by creating a streamlined and efficient interface.Accomplishments include: • Directed architectural design decisions and fine-tuned end-to-end application functionality; achieved a 40% reduction in system response time, resulting in improved user experience and increased customer satisfaction. • Designed, developed, and maintained Ratio Launcher Android application. • Exceeded premium users by 25-35% through excellent animations and user friendly UI. • Implemented Jetpack Compose for building different Ratio card widgets. • Architected my code to be efficient, multi moduled, reliable, maintainable and reusable. • Refined smooth Animation with Motion Layout & improved overall performance of app. • Tested the application on different android phones, and tablets, debugged on a real devices,and debugged the issues that were found. • Implemented Jetpack Compose for different ratio card widgets, achieved butter smooth animation & and achieved pixel-perfect UI using Jetpack Compose. • Facilitated to engineering best practices, guidelines, and our technical infrastructure to help enhance infrastructure and improve reliability and efficiency.Tech Stacks: #Java #Kotlin #Gradle #AndroidX #CI/CD #Dagger & Hilt #Kotlin Coroutines # Kotlin Flow #Room #LiveData #VIewModels #JSON (REST) APIs #Retrofit #Model-view-viewmodel (MVVM) #Moshi #Systems Design #Android Navigation Component #Github Actions for CI/CD processes #JUnit, Mockito and Jacoco for reports, #Firebase: For Analytics, remote config, cloud functions and crashlytics. #Functional Programming.

London, England, United Kingdom

Nearcut offers features such as online booking, appointment reminders, customer management, and other tools that can enhance the overall efficiency of a barbershop or salon. Customers can book appointments online, and businesses can benefit from features that simplify scheduling, reduce no-shows, and provide a better experience for both clients and staff.Accomplishments include:• Developed Card Reader App for Barbers using Stripe Terminal SDK.• Developed the full application from scratch and deploy it in play store. • Write full suite of Unit & UI test cases with 90% test coverage.• Optimized code base through proactive refactoring and rigorous code review, resulting in a 50% reduction in bug frequency and doubling the maintainability of the source code, leading to enhanced development efficiency and faster feature implementation.• Fixed critical bugs and users support.• Applied flavor for supporting 2 apps with different package name. • Upgrade terminal SDK time to time.• Fixed reported critical bugs & crash from Firebase crashlyticsTech Stacks:# Kotlin# XML# Stripe Terminal SDK# Bluetooth BLE# UI# Animations# Dagger2# Coroutines# Kotlin Flow# Rollbar# TDD(Test Driven Development)

United States

tawk.to is a free live chat app that lets us monitor and chat with visitors on your website or from a free customizable page. As an Android Developer, my responsibility was to develop core features and help other developers in maintaining and improving application.Accomplishments include:• Led the development of game-changing features in the Tawk.to app, resulting in a 50% reduction in app loading time and a 40% increase in user acquisition.• Developed new features in Tawk.to app that impact millions of users.• Fixed critical crashes which help reducing crash free users by 10%.• Implemented individually as well as part of a larger team.• Developed of various modules in accordance with Agile Methodology framework.• Collaborated along with the Business Analysis, Design, QA, and Development team in shaping the product as per the Customers requirements• Developed key functionalities like on middleware side, Database design, Android framework for multiple device support• Led codebase enhancement initiatives by actively refactoring and reviewing code, resulting in a 2x increase in code maintainability, reduced technical debt, and improved development efficiency, ensuring seamless collaboration among team members and delivering high-quality software solutions.• Architectured for a better UI and performance and my responsibilities included the below:• Implemented Search feature: Implemented search feature for searching notes and contacts.• Coded the feature to save conversation: This feature allows users to save the entire conversation in a vault. This demanded in-depth knowledge of Rx Java, as the list had to be populated reactively.• Moved less important activities to Kotlin: Some parts of the project were moved to Kotlin and it involved learning a new language quickly and writing small pieces of code.Tech Stacks:# Kotlin# Java# Clean Architechture# MVVM# MVP# RxJava# Flow# Kotlin coroutine# Koin# Twilo (for Voice & Video Call)

New York, United States

USECRYPT is a secured messaging app. It created its own systems that make it possible to hold encrypted messages and calls in HD standard. Whole communication via usecrypt messenger is secured with end‑to‑end encryption with all cryptographic operations made on user’s device.Accomplishments include:• Engineered and implemented performance-enhancing features from the ground up, adhering to industry-standard coding practices and architectural principles; achieved a 40% reduction in app response time and improved overall user experience.• Designed and implemented robust end-to-end encryption mechanisms to secure user communications.• Stayed informed about the latest encryption standards and best practices.• Implemented secure data storage practices, including encrypted local storage for sensitive user data.• Chose and implemented secure communication protocols to protect data during transit.• Implemented secure UI components to protect against common vulnerabilities like input validation issues.• Implemented secure push notification mechanisms,ensure that notifications do not expose sensitive information.• Developed Voice calls using Web-RTC, encryption, decryption using OMEMO, AXOLOTL. • Completed understanding of XMPP, EJABBERED• Optimized the app's performance without compromising security.• Stayed updated on the latest trends, tools, and best practices in mobile app security.• Optimising app performance and elevating user experience and I exceeded the expectation of my client.Tech Stacks:#Java#Sqlcipher#Omemo#Axolotl#XMPP#Ejabberd#RxJava#Event Bus#Web-RTC#Android Jetpack#LiveData

Dhaka, Bangladesh

Topcoder is a platform that hosts competitive programming contests and challenges. Topcoder offers a variety of gigs, the gig I excelled here as an Android Developer for Robinhood App, a popular app for food & hotel services in Thailand.Accomplishments include:• Implemented systematic code review practices and conducted regular refactoring sessions, resulting in a 50% reduction in technical debt, improved code readability, and a more scalable and maintainable codebase, enhancing team productivity and reducing time spent on bug fixes.• Led codebase enhancement initiatives by actively refactoring and reviewing code, resulting in a 2x increase in code maintainability, reduced technical debt, and improved development efficiency, ensuring seamless collaboration among team members and delivering high-quality software solutions.• Impemented Flutter modules of Robinhood Super app • Integrated Adzerk SDK for digital advertising• Connected flutter module with Native side• Developed and improved UI for hotel and food search• Created Unit test cases using Mockito• Collaborated with web services team to implement the backend support.• Improved code base through continuous refactoring & code review of other developer's code.Tech Stacks:#Kotlin#Flutter#Dart#MVVM#OOP#Dagger2

Romania

Wesrom Corporation is a Software Development and Digital Marketing Company. As a Senior Mobile Developer, my responsibility was to work on their various client projects for Wesrom.Accomplishments include: • Maintained multiple client applicationsin Native Android, React Native & Flutter • Replaced Java & RxJava by Kotlin and Coroutines. • Achieved desired results within a specific timeframe. • Facilitated in deciding Architecture Design for several apps. • Guided other developers • Introduced Kotlin, Navigation Jetpack, and MVVM Architecture in the project. • Performed bug fixes and improve overall application performance. and how they applyto mobile applications. • Implemented Push Notifications FCM to send users information based on deals and their reservations. • Debugged issues that were found during different phases of the project using android tools and fixed them.Tech Stacks: # Java # Kotlin # Sqlite # Typescript # Javascript # React Native # React JS # Dart # Flutter # Bloc # OOP # Object-Oriented Programming (OOP) # Mobile Application Development # HTML # MYSQL # XML # Cascading Style Sheets (CSS) # Xcode # Swift (Programming Language) # iOS Development

Dubai, United Arab Emirates

Borndigital Limited had its product Anom which is an FBI-backed secured messaging application. Accomplishments include:• Participated in Cross-team collaboration, with product, design, and QA teams, to ensure we create great user experiences whilst also adhering to high security and privacy standards which are underpinned by our end-to-end encryption• Designed and developed custom field communications solutions, based on encrypted Push-to-Talk platform.• Implemented integration with Amazon AWS for uploading and downloading media files.• Created and incorporated SQLCipher database Manager for local data persistence of audit files on the device.• Analyzed standard Android components activities, services, database, layout as well as creating custom views for the application.• Designed and created UI, sound, and haptic feedback based on client requirement• Identified issues and bugs increased the bug-free users from 84% to 97%• Implemented Voice calls using Web-RTC, encryption, decryption using OMEMO, AXOLOTL. • Completed understanding of XMPP, EJABBERED• Implemented block and multi-threaded based programming concepts in the code.• Identified and fixed any bugs reported during the testing phase of the project. • Introduced Kotlin, Navigation Jetpack, MVVM Architecture in the project.• Developed Android JUnit Extensions for writing test cases.• Implemented Push Notifications FCM to send users information based on deals and their reservations.• Tested the application on different android phones, tablets, debugged on real devices, and debugged the issues that were found.• Re-organized and architectured for a better UI and performance Tech Stacks:#Java#Kotlin#Sqlcipher#Omemo#Axolotl#XMPP#Ejabberd#RxJava#Event Bus#Web-RTC#Android Jetpack#LiveData

Dhaka, Bangladesh

Oceanzie Inc is a Japanese Company, i excelled in various projects in Oceanize Inc.Accomplishments include: • Recorded every project meeting and wrote down into a report, coordinate with the Project Manager on current project tasks. • Identified and fixed any bugs reported during the testing phase of the project. • Wrote project report every phase that follows the project process. • Development of various modules in accordance with the Agile Methodology framework. • Involved in Application testing, Memory Analysis, Screen fragmentation support. • Hands on Experience with video streaming technologies like HLS, DASH with adaptive bitrate streaming and video encoding/decoding. • Detected and fixed memory leaks. • Involved in designing the interface along with the Design and UX team for better usability and handling across iOS and Android and maintain their relative nativity. • Attended daily standup meetings, discussing the work accomplished, planned, • Involved in the full life cycle of the project including analysis design, development, debugging, testing, and deployment. • Deployed prototypes of the app for hands-on user testing • Developed features from scratch following coding standards and Architectures. • Improved code base through continuous refactoring & code review of other developer's code. • Performed bug fixes and improve overall application performance. • Responded to client needs for applications with an eye to the most feasible and effective solutions. • Collaborated and coordinated with iOS developer counterparts and backend

Dhaka, Bangladesh

Accomplishments include:• As the only Android developer for the company, quickly jumped on board and took full responsibility of the development and operation of the app.• Performed bug fixes on existing code and analyzed existing code to detect and fix code.• Implemented login system using Firebase.• Integrated Retrofit for better and parallel network calls.• Collaborated with web services team to implement the backend support.• Encrypted data safely on device and use the Android Keystore

Dhaka, Bangladesh

Accomplishments include:• Developed various modules in accordance with Agile Methodology & framework.• Collaborated along with the Business Analysis, Design, QA, and Development team in shaping the product as per the Customers requirements• Developed of key functionalities like on middleware side, Database design, Android framework for multiple device support• Conducted product to demonstrate the project to multiple clients JAVA• Coded using java methodologies.