Mehedi Hasan Khan, Developer in Dhaka, Dhaka Division, Bangladesh
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Mehedi Hasan Khan

Verified Expert  in Engineering

Software Engineer and Developer

Location
Dhaka, Dhaka Division, Bangladesh
Toptal Member Since
November 13, 2013

Mehedi is a top software engineer who builds delightful mobile apps and related software systems. With nearly a decade of experience designing, architecting, and developing native Android and iOS apps, he has gained expert knowledge of Android/iOS systems, SDLC, Java, Swift, Kotlin, REST APIs, Scrum, clean architecture, and more. Mehedi is a team player and master communicator with a curious mind and an entrepreneurial mindset.

Portfolio

Eastside Healthcare Staffing LLC
iOS, Android, Kotlin, Mobile, TypeScript, Hybrid Apps...
Zero Longevity Science
Kotlin, Android, Android Studio, Android Jetpack, Coroutines, Jetpack Compose...
Zero Longevity Science
Kotlin, Android, Model View ViewModel (MVVM), Android Jetpack, Jira, REST APIs...

Experience

Availability

Part-time

Preferred Environment

MacOS, Xcode, Android Studio, Linux, Agile Software Development, Android, iOS, IntelliJ IDEA, Jira, Git

The most amazing...

...app I've helped build is called Zero, a revolutionary fasting tool and healthy living companion loved by millions.

Work Experience

Mobile Engineer

2023 - 2023
Eastside Healthcare Staffing LLC
  • Added single sign-on (SSO) to UKG using Okta as the identity provider and updated the Android and iOS apps to enable single sign-on.
  • Developed a reliable location tracking system that can track the location of a clinician's phone during their shifts at regular intervals. The system can work offline and log locations even if the app is not running.
  • Built a CI/CD system using GitHub Actions and Xcode cloud to develop and deploy apps to Firebase app distribution, TestFlight, and respective app stores.
  • Took the apps through the Play Store and App Store's review process. Made changes and implemented reasonable workarounds to approve the apps (with their requirements for background execution and long-term location tracking).
Technologies: iOS, Android, Kotlin, Mobile, TypeScript, Hybrid Apps, Progressive Web Applications (PWA), Swift, Mobile App Development

Software Engineer III

2021 - 2022
Zero Longevity Science
  • Put together a guideline and coded a foundational framework for incorporating Jetpack Compose into the project to build all new UIs.
  • Prepared a presentation introducing the Compose framework and its different aspects and presented it to the Android team so that other team members could get up to speed with the new technology.
  • Refactored the client-side reminder engine for storing and scheduling all local notifications, making it more efficient and capable of executing asynchronously in a thread-safe way and avoiding unnecessary loading or retention of data.
  • Rebuilt screen containing tons of charts and stats using Jetpack Compose; UI rendering got twice as fast. Optimized data loading (using co-routines) and retention (non-UI data were cached to a room database). Memory footprint reduced by around 60%.
  • Reviewed PRDs and designs to provide early feedback and technical opinions on feasibility, probable implementation paths, and implications. Wrote TDDs and Jira tickets for complex features.
  • Designed a new Git workflow (based on Gitflow) to make code reviews and releases easier by discouraging cherry-picking. Tweaked the existing release process to be more automated (using GitHub Actions and CircleCI) and streamlined.
Technologies: Kotlin, Android, Android Studio, Android Jetpack, Coroutines, Jetpack Compose, Model View ViewModel (MVVM), Jira, Prismic, Benchmarking, Performance, Memory Profiling, Agile, Figma, Notion, Miro, Monday.com, Gradle, Python, Dagger 2, Clean Code, Retrofit 2, Amplitude, Apptimize, Firebase, Cloud Firestore, CircleCI, LiveData, Location Services, Material 2, Lottie, Google Fit, Fitbit API, JSON Web Tokens (JWT), Facebook SDK, Firebase Authentication, Charts, MPAndroidChart, ExoPlayer, Camera2 API, AppsFlyer, Zendesk, Subscriptions, Slack, Google Play Store, Release Management, Git, GitHub, Scripting, LeakCanary, Espresso, Mockito, Unit Testing, Product Requirements Documentation (PRD), Code Review, Mentorship, APIs, User Experience (UX), User Interface (UI), Android Animations, Integration Testing, CI/CD Pipelines, OkHttp, Architecture, Leadership, Mobile Applications, Flutter, Dart, API Integration, GraphQL, Amazon Web Services (AWS), Microservices, WebSockets, System Architecture, Technical Leadership, Algorithms, Android SDK, RESTful Web Services, Cryptography, SQL, REST APIs, SQLite, Google Maps, Facebook API, Xcode, Agile Software Development, C++, AI Programming, Machine Learning, Dagger, Social Media Integration, Multithreading, Software Architecture, Reactive Streams, Mobile Security, Object-oriented Programming (OOP), Google Gson, REST, SOLID Principles, Database Modeling, Design Patterns, Socket Programming, OpenSSL, Cache, Encryption, Geolocation, Regular Expressions, GPS, RxJava, Programming, Software Engineering, Databases, Payment APIs, Camera API, Mobile GPS, Mobile Payments, Firebase Android SDK, Video Streaming, Audio Streaming, Mobile App Development

Software Engineer

2019 - 2021
Zero Longevity Science
  • Took the initiative to make a single activity architecture cleaner by using Android Jetpack architecture components and conforming more strictly to MVVM.
  • Composed a guideline and roadmap to use Kotlin coroutines appropriately for async operations and replace the existing callback-based way of doing async tasks where applicable.
  • Took ownership of complex feature implementations, i.e., challenges, personalized fasting zones, etc. Communicated across teams to clarify requirements, update documentation, and help with on-time completion.
  • Put together a CI/CD system equipped with Git hooks, Gradle plugins, and Python scripts for uniform code formatting and styling, code quality checks, report generation, automated testing, and release.
  • Created a framework for building complex dynamic forms with configurable data validation, caching, and submission features.
  • Developed a framework for A/B tests to work with both Firebase and Apptimize.
  • Built a framework for faster development of new paywalls with support for A/B tests, offers, and campaigns.
Technologies: Kotlin, Android, Model View ViewModel (MVVM), Android Jetpack, Jira, REST APIs, Prismic, Agile Software Development, Figma, Notion, Miro, Monday.com, Android Studio, Gradle, Python, Clean Code, Dagger 2, Coroutines, Retrofit 2, Amplitude, Apptimize, Firebase, CircleCI, Firebase Android SDK, LiveData, Material 2, Lottie, Cloud Firestore, Google Fit, JSON Web Tokens (JWT), Facebook SDK, Charts, MPAndroidChart, ExoPlayer, Camera2 API, Subscriptions, AppsFlyer, Zendesk, Slack, Scripting, LeakCanary, Espresso, Mockito, Unit Testing, APIs, User Experience (UX), User Interface (UI), Android Animations, Video Streaming, Audio Streaming, Integration Testing, CI/CD Pipelines, OkHttp, Architecture, Mobile Applications, Flutter, Dart, API Integration, GraphQL, Amazon Web Services (AWS), Microservices, WebSockets, Technical Leadership, Algorithms, Git, Android SDK, RESTful Web Services, Cryptography, SQL, GitHub, SQLite, Google Maps, Facebook API, Xcode, C++, Dagger, Social Media Integration, Multithreading, Software Architecture, Reactive Streams, Mobile Security, Object-oriented Programming (OOP), Google Gson, REST, SOLID Principles, Database Modeling, Design Patterns, Socket Programming, OpenSSL, Cache, Encryption, Geolocation, Regular Expressions, GPS, Location Services, RxJava, Programming, Software Engineering, Agile, Databases, Payment APIs, Camera API, Mobile GPS, Mobile Payments, Jetpack Compose, Benchmarking, Performance, Memory Profiling, Firebase Authentication, Google Play Store, Release Management, Product Requirements Documentation (PRD), Code Review, Mentorship, Mobile App Development

Software Engineer

2019 - 2019
Duolingo
  • Developed new features specifically targeted to users in China—for example, user signup via WeChat, share via WeChat and earn rewards, etc.
  • Created A/B tests to battle-test new features, UX changes, optimizations, etc.
  • Wrote custom UI components—for example, a UI widget that can take country code and phone number input, validate it on the fly, and then transform it for verification code input.
  • Implemented fluid animations with Lottie, and optimized animation loading, replay, and memory footprint.
  • Examined memory usage to find possible optimization points, memory leaks, etc., and fixed them.
Technologies: RxJava, Lottie, Android, Kotlin, REST, Clean Code, Agile Software Development, Android SDK, RxJava 2, APIs, User Experience (UX), User Interface (UI), Android Animations, Model View ViewModel (MVVM), Integration Testing, CI/CD Pipelines, Retrofit 2, OkHttp, Mobile Applications, Amazon Web Services (AWS), Microservices, WebSockets, Git, RESTful Web Services, REST APIs, GitHub, Facebook API, Jira, Python, Dagger, Social Media Integration, Multithreading, Software Architecture, Reactive Streams, Mobile Security, Object-oriented Programming (OOP), Google Gson, SOLID Principles, Gradle, Design Patterns, Reactive Extensions, Reactive Programming, Dagger 2, OpenSSL, Functional Reactive Programming, Cache, Unit Testing, Programming, Software Engineering, Agile, Android Jetpack, Figma, Slack, Scripting, Benchmarking, Performance, Memory Profiling, Code Review, Mobile App Development

Android/iOS Developer

2018 - 2018
iVerified
  • Improved the scanning of physical identity documents using the device camera by optimizing the detection and processing pipeline.
  • Used OpenCV and machine learning to detect ID documents better and classify the data.
  • Used Tesseract to extract data from image segments.
  • Designed and implemented a two-way data sync process, ensuring that the documents and verification data were securely kept in sync between the server and the apps.
  • Set up continuous deployment (testing, building, signing, and releasing) with Fastlane and a remote Jenkins server.
Technologies: Tesseract, Core ML, OpenCV, Swift, Java, iOS, Android, Android SDK, iOS SDK, RxJava 2, Cocoa Touch, APIs, User Experience (UX), User Interface (UI), Cryptography, Secure Storage, Decentralized Applications, Model View ViewModel (MVVM), Integration Testing, CI/CD Pipelines, App Store, TestFlight, Retrofit 2, OkHttp, Mobile Applications, API Integration, Artificial Intelligence (AI), System Architecture, Git, RESTful Web Services, REST APIs, Xcode, CocoaPods, ReactiveCocoa, Jira, OAuth, Computer Vision, Security, Machine Learning, Python, RxSwift, Software Architecture, Mobile Security, Object-oriented Programming (OOP), Google Gson, SOLID Principles, Gradle, UIKit, Design Patterns, Reactive Extensions, Reactive Programming, Socket Programming, Dagger 2, Protobuf, Functional Reactive Programming, Encryption, Regular Expressions, Image Processing, Fabric, Programming, Software Engineering, Agile, Data Encryption, Camera API, Slack, Scripting, Google Play Store, Release Management, Code Review, Stripe, Mobile App Development

Senior Android/iOS Developer

2017 - 2018
A0Paper Inc.
  • Wrote SDKs in Java and Swift for Treasuredata based on their official SDK. Improved local caching, optimized memory usage, added scheduled batch uploads in the background, and improved the fluidity of the API.
  • Wrote the 1stScreen SDK for Android (Java) and iOS (Swift) to help collect numerous analytics data, with device data collection made easier and a default fallback strategy for cases when hardware or permission might be unavailable.
  • Deployed and released the Android SDK to a private Maven repository so that only authorized developers could access the SDK.
  • Deployed and released the iOS SDK to a private CocoaPods repository so that only authorized developers could access the SDK. The library is distributed as a binary.
  • Built a reusable ad component that could be embedded in-app content and reveal itself upon scrolling as per the set criteria.
Technologies: Gradle, CocoaPods, Apache Maven, iOS, Android, Swift, Java, Android SDK, iOS SDK, Cocoa Touch, Retrofit 2, OkHttp, React Native, API Integration, Git, Xcode, JavaScript, RxSwift, Multithreading, Software Architecture, Object-oriented Programming (OOP), SOLID Principles, UIKit, Design Patterns, Functional Reactive Programming, Programming, Software Engineering, ExoPlayer

Lead Engineer

2016 - 2018
Credntia
  • Led the planning, architecture, development, scaling, and deployment of the Android and iOS apps.
  • Chose a new architecture (VIPER) for the iOS app for better performance and suggested new DBMS and security enhancement for proper encryption and data protection.
  • Designed and implemented a new clean architecture for the Android app for better performance, stability, and scale. Used Dagger 2 for dependency injection, RxJava, and reactive extensions for reactive programming support.
  • Worked on achieving HIPAA compliance for the Android and iOS apps. All sensitive data were protected with 256-bit AES encryption, stored locally, and covered with two layers of authentication-based security.
  • Collaborated with the team to design data structure and infrastructure for the Parse and Firebase (later) back end.
  • Worked with the team to design a secured REST API for third parties.
  • Developed a new barcode scanner library for Android based on Google's Mobile Vision API, especially for reading PDF417 barcodes more accurately and faster than ZXing.
  • Created an OpenCV-based mobile vision library that can detect ID documents (e.g., passport and driver's license) in real-time using the device camera.
Technologies: Dagger, Realm, Mixpanel, Fabric, RxSwift, RxJava, JSON Web Tokens (JWT), Swift, Java, OpenCV, Encryption, Firebase, iOS, Android, Mobile Payments, Android SDK, iOS SDK, Cocoa Touch, APIs, User Experience (UX), Subscriptions, User Interface (UI), Android Animations, Cryptography, Secure Storage, HIPAA Compliance, UIKit, Model View ViewModel (MVVM), Viper, CI/CD Pipelines, App Store, TestFlight, Retrofit, OkHttp, Architecture, Leadership, Mobile Applications, API Integration, Artificial Intelligence (AI), System Architecture, Technical Leadership, Algorithms, Git, RESTful Web Services, SQL, REST APIs, GitHub, SQLite, Facebook API, Xcode, CocoaPods, Agile Software Development, ReactiveCocoa, OAuth, Computer Vision, C++, Security, Social Media Integration, Multithreading, Software Architecture, Reactive Streams, Mobile Security, Object-oriented Programming (OOP), Google Gson, REST, SOLID Principles, Database Modeling, Gradle, Core Data, X (formerly Twitter) API, Design Patterns, Reactive Extensions, Reactive Programming, OpenSSL, Cache, Regular Expressions, Image Processing, Programming, Software Engineering, Databases, Payment APIs, Data Encryption, Camera API, Bluetooth, Mobile GPS, Clean Code, Firebase Android SDK, Facebook SDK, Benchmarking, Performance, Firebase Authentication, Google Play Store, Release Management, Product Requirements Documentation (PRD), Code Review, Mentorship, Back-end, Bluetooth Low Energy (LE), Near-field Communication (NFC), Mobile App Development

Lead Engineer

2015 - 2017
PartyLife
  • Did requirement analysis with the founders and made a detailed technical specification.
  • Designed the system architecture and defined the infrastructure components based on the requirements and business goals.
  • Wrote a detailed specification for the required back-end service and led the web team to build a robust REST API.
  • Developed the native Android and iOS apps with social features like profiles, messaging, search, etc.
  • Designed the continuous development, internal testing, and deployment pipeline for continuous improvement of the platform.
Technologies: Cache, REST, SQLite, Facebook API, ZOOZ API, Location Services, Google Maps API, MySQL, iOS, Android, Swift, Java, Mobile Payments, Android SDK, iOS SDK, Cocoa Touch, APIs, User Experience (UX), Subscriptions, User Interface (UI), Android Animations, UIKit, App Store, TestFlight, CTO, Architecture, Leadership, Mobile Applications, API Integration, System Architecture, Technical Leadership, Git, RESTful Web Services, SQL, REST APIs, Google Maps, Xcode, MapKit, CocoaPods, RxSwift, Social Media Integration, Multithreading, Software Architecture, Object-oriented Programming (OOP), Google Gson, SOLID Principles, Database Modeling, Bitbucket, Model View Controller (MVC), Core Data, Design Patterns, Geolocation, GPS, Fabric, Mixpanel, Programming, Software Engineering, Databases, Maps, Payment APIs, Mobile Navigation, Camera API, Mobile GPS, Facebook SDK, Google Play Store, Release Management, Product Requirements Documentation (PRD), Back-end, Bluetooth Low Energy (LE), Near-field Communication (NFC), Retrofit, Stripe, Instant Messaging, Mobile App Development, Social Media Apps

Independent Android/iOS Developer

2011 - 2017
Freelance
  • Developed an Uber-like taxi booking system with separate apps for drivers and passengers. Riders could filter locally available cars based on their types and features, communicate with drivers in real-time, and pay with a card for the ride.
  • Developed an Android app used to facilitate and track the delivery of packages. Delivery reports were digitally signed, and a web dashboard provided tracking, verification, and review capabilities.
  • Developed an Android app for finding childcare services. Users could perform location-based searches, read client reviews, and contact childcare centers. Further, the app provided driving directions and real-time navigation to childcare centers.
  • Implemented several image warping algorithms on Android, including bulge effect, explosion, implosion, etc.
  • Developed an Android app for budget tracking and automatic budget population, using user data (e.g., location, profession, income, budget, and expense history) and statistical models to generate an optimal budget for maximizing savings.
  • Developed an Android app for a security company facilitating reporting and supervision of guard patrol activities, routes, arrests, or incidents. GPS and cameras were utilized to capture important location and incident data.
  • Utilized Git and Jira for source control and issue tracking. Developed using MVC with Agile methodologies.
  • Developed an Android app that allowed users to take or upload photos and apply basic filters before sharing them on Facebook and Twitter. Further, users could schedule their posts to upload at a particular time.
Technologies: XML, SQL, Swift, iOS, Java, Android, Agile Software Development, Git, Maps, Geolocation, Payment APIs, XMPP, Mobile Navigation, Data Encryption, Camera API, Bluetooth, Mobile GPS, REST, TestFlight, Google Maps, iOS SDK, Oracle PL/SQL, Objective-C, Spring Boot, Social Media Integration, Bitbucket, Model View Controller (MVC), Jackson, Eclipse IDE, X (formerly Twitter) API, Ejabberd, IntelliJ IDEA, HTML, Location Services, MacOS, Mixpanel, Programming, Databases, Firebase Android SDK, Facebook SDK, ExoPlayer, Slack, Google Play Store, Release Management, Video Streaming, Audio Streaming, App Store, Mobile App Development, Social Media Apps

Lead Android/iOS Developer

2013 - 2015
Cabeze
  • Developed Android and iOS apps for an Uber-like service. Developed both driver and passenger apps.
  • Developed innovative UI libraries (sliding drawers, floating views, etc.) to build a modern yet smooth user experience.
  • Utilized Google Maps API and device's GPS for optimized turn by turn driving navigation and ETA calculation.
  • Developed, tested, and optimized data refresh strategy for maps to provide an almost real-time experience.
  • Developed, tested, and optimized a push- and pull-based communication strategy between driver and passenger apps to ensure a smooth overall experience.
  • Integrated payment gateways, e.g., PayPal and credit/debit cards.
Technologies: PayPal API, Geolocation, SQLite, REST, Objective-C, Java, iOS, Android, Mobile Payments, Android SDK, iOS SDK, APIs, User Interface (UI), Android Animations, App Store, CTO, Architecture, Leadership, Mobile Applications, API Integration, System Architecture, Technical Leadership, Algorithms, Git, RESTful Web Services, REST APIs, Google Maps, Xcode, Swift, MapKit, CocoaPods, Cocoa Touch, OAuth, Google Maps API, Multithreading, Software Architecture, Object-oriented Programming (OOP), Database Modeling, Model View Controller (MVC), Jackson, Eclipse IDE, Core Data, Design Patterns, Waterfall Development, GPS, Location Services, Programming, Databases, Maps, Payment APIs, Mobile Navigation, Mobile GPS, Google Play Store, Release Management, Retrofit, Mobile App Development

Android Developer

2013 - 2013
Handup
  • Developed a collaborative voting app for secure voting.
  • Developed a text input control based on Edittext that could identify, categorize, and validate entered text using regular expressions and showed added items as chips (https://material-ui.com/demos/chips/).
  • Developed a UI widget that allowed the user to drag and drop the items, e.g., voting options, to reorder and merge in order rank the options.
  • Wrote a horizontal bar chart widget and a pie chart widget to show voting statistics in an interactive way.
  • Developed a statistical ranking algorithm and implemented that for ranked votes.
  • Used geofencing for notifying users when they are in a designated voting location. Used GPS and other location APIs to filter ongoing location-based votings.
Technologies: GPS, Google Maps API, SQLite, REST, Regular Expressions, OpenGL ES, Java, Android, Android SDK, APIs, User Interface (UI), Android Animations, Architecture, Mobile Applications, API Integration, WebSockets, Algorithms, Git, RESTful Web Services, Cryptography, REST APIs, Google Maps, PayPal API, Social Media Integration, Model View Controller (MVC), Jackson, Eclipse IDE, X (formerly Twitter) API, Design Patterns, Waterfall Development, Geolocation, Location Services, Programming, Maps, Mobile GPS, Subscriptions, Google Play Store, Mobile App Development

Credntia

Credntia is the missing piece of your digital wallet. The app can scan identification documents (driver’s license, passport, etc.) and store them securely. Computer vision and OCR are used to scan the documents. 256 bit AES encryption is used to keep all local data secured.

iVerified

The ultimate free, simple, safe, and reusable identity and age verification app for Android and iOS.

PartyLife

I developed the Android and iOS apps for the social dating platform for party lovers called PartyLife.

Cabeze Taxi

This taxi booking system consists of two Android apps: one for the passenger, and another for the driver. Passengers can search for nearby taxis by choosing pickup and destination locations. The search results can be filtered by car type. After a client sends out a request, nearby taxi drivers are notified through the app, after which they accept or decline the request. Upon acceptance of the job, the passenger is granted access to information about the driver and can view the driver's progress in real time using live navigation on a map. Both the passenger and the driver can communicate with each other via the app. Finally, the passenger can pay through the app by credit card or with PayPal, as well as rate the driver's service.

Handup

I developed the Android version of the collaborative voting and decision making app called Handup.

Secured Preference Store

https://github.com/iamMehedi/Secured-Preference-Store
A cryptography library and a SharedPreferences wrapper for Android that encrypts the content with 256-bit AES encryption. The encryption key is securely stored in the device's KeyStore and protected by the device's passcode.

CVScanner

https://github.com/Credntia/CVScanner
An OpenCV-based library for Android to scan ID documents or passports. It uses an optimized processing pipeline to process live camera frames in the background. It can detect the edges of a document, crop the document from the camera frame/photo, transform it for readability, and do some basic data validation.

StepBuilder Generator

https://plugins.jetbrains.com/plugin/8276-stepbuilder-generator
IntelliJ IDEA/Android Studio plugin to generate a builder class following the Step Builder pattern.

MVBarcodeReader

https://github.com/Credntia/MVBarcodeReader
A barcode scanner library for Android. Uses the Google Play Services' mobile vision API for barcode detection.

Barnc

This is a complete data backup and social business platform. The Android app lets you back up all your device data, i.e., contacts, photos, media, etc., to its own server or Dropbox/Box/Onedrive. The user can create a business profile along with digital business cards and then share those cards or any other media from within the app with his business associates. There is also a real-time text, audio, and video chat system through which the user can conduct meetings.

Astraea - Law Farm Management System

A distributed database system developed in C# using .NET Windows Forms and an Oracle DB. The software provides a system for law firms to manage case files and client information. Administrators can assign cases to groups or individuals through the system and keep track of case progress. Further, the software includes an accounting system to track the firm's payments. The system has a public notice board as well as an internal messaging system. Additional discussion threads can be opened for any issue. Finally, a scheduling system was also implemented for members, clients and cases, which notifies respective parties via email and SMS when a task is scheduled.

Automated Budget Planner

Generates budget proposals based on user income and expense data, with the help of statistical data from a database.

Childcare Finder

This Android app provides information about childcare or day care facilities. Users can search for nearby facilities by address, postcode, or a location chosen on a map. Reviews of each service provider are also displayed, as well as driving directions to a chosen facility. In addition, users can rate or review service providers.

Social Automator

This Android app enables users to post text or images to Facebook and Twitter from their device. Users can schedule certain text or images to be shared at a certain time through their Facebook or Twitter accounts.
2008 - 2013

Bachelor of Science Degree in Computer Science and Engineering

Bangladesh University of Engineering and Technology - Dhaka, Bangladesh

2005 - 2007

Higher Secondary Certificate Degree in Science

Notredame College - Dhaka, Bangladesh

AUGUST 2022 - AUGUST 2024

IELTS

British Council

Libraries/APIs

RxJava, RxSwift, Fabric, Google Maps API, Reactive Extensions, Google Gson, REST APIs, CocoaPods, Google Maps, Facebook API, X (formerly Twitter) API, PayPal API, Jackson, Camera API, Retrofit 2, Firebase Android SDK, LiveData, Material 2, Facebook SDK, MPAndroidChart, LeakCanary, RxJava 2, Retrofit, Protobuf, OpenCV, OpenSSL, Camera2 API, Stripe, OpenGL ES, JavaMail, Fitbit API

Tools

Bitbucket, GitHub, Git, Xcode, Android Studio, Gradle, IntelliJ IDEA, Jira, Eclipse IDE, Android Jetpack, Figma, CircleCI, ExoPlayer, Slack, Firebase Authentication, TestFlight, Microsoft Visual Studio, Notion, Apache Maven, Miro

Frameworks

Dagger, Dagger 2, ReactiveCocoa, Android SDK, iOS SDK, MapKit, UIKit, Core Data, Cocoa Touch, JSON Web Tokens (JWT), Spring Boot, .NET, Viper, Flutter, Core ML, Espresso, Mockito, React Native

Languages

Kotlin, SQL, Swift, Java, JavaScript, GraphQL, C, C#, Objective-C, Python, C++, Dart, XML, CSS, HTML, TypeScript

Paradigms

Reactive Programming, REST, Model View Controller (MVC), Object-oriented Programming (OOP), Agile Software Development, Design Patterns, Agile, Clean Code, Model View ViewModel (MVVM), HIPAA Compliance, Functional Reactive Programming, Socket Programming, Unit Testing, Microservices, Waterfall Development, Management

Platforms

Firebase, Mixpanel, iOS, Android, Windows, Ubuntu, MacOS, Oracle, AppsFlyer, Bluetooth Low Energy (LE), Amazon Web Services (AWS), Linux, Java EE, Zendesk, Mobile

Storage

Realm, Cache, SQLite, Database Modeling, Oracle PL/SQL, MySQL, Databases, Cloud Firestore, Microsoft SQL Server

Other

Encryption, Geolocation, GPS, Location Services, Reactive Streams, Social Media Integration, User Experience (UX), SOLID Principles, Algorithms, Cryptography, Mobile Security, Data Structures, Software Architecture, XMPP, RESTful Web Services, Multithreading, Security, OAuth, Programming, Operating Systems, Software Engineering, English, Maps, Payment APIs, Mobile Navigation, Data Encryption, Mobile GPS, Mobile Payments, Coroutines, Apptimize, Subscriptions, Jetpack Compose, Performance, Google Play Store, Release Management, Code Review, APIs, User Interface (UI), Android Animations, Secure Storage, CI/CD Pipelines, App Store, Architecture, Mobile Applications, API Integration, System Architecture, Technical Leadership, Mobile App Development, Social Media Apps, Regular Expressions, Image Processing, Lottie, Computer Vision, Artificial Intelligence (AI), Ejabberd, VoIP, Machine Learning, Networking, Bluetooth, Prismic, Amplitude, Google Fit, Charts, Scripting, Benchmarking, Memory Profiling, Product Requirements Documentation (PRD), Mentorship, Back-end, Near-field Communication (NFC), Video Streaming, Audio Streaming, Integration Testing, OkHttp, CTO, Leadership, WebSockets, Instant Messaging, ZOOZ API, Tesseract, Deep Learning, Network Programming, AI Programming, Graphics, Discrete Mathematics, Computational Geometry, Mathematics, Physics, Chemistry, Biology, Monday.com, Decentralized Applications, Hybrid Apps, Progressive Web Applications (PWA)

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