John Ernest Guadalupe, Developer in Santo Tomas, Calabarzon, Philippines
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John Ernest Guadalupe

Verified Expert  in Engineering

Bio

John is a seasoned professional dedicated to delivering impactful, user-centered solutions that align with client goals. With a focus on transforming innovative concepts into market-ready products, he consistently develops high-quality solutions that drive measurable business success.

Portfolio

EY
React Native, Kotlin, Android, AngularJS, Xamarin.Forms, SQL Server, Azure...
Freelance Work
Android, Technical Leadership, Android SDK, Kotlin, Android, C#, GraphQL...
Orion180 Insurance Services LLC
Xamarin, .NET, C#, JavaScript, HTML, CSS, Database, Mobile UI Design...

Experience

Availability

Full-time

Preferred Environment

Android Studio, Visual Studio, Visual Studio Code (VS Code), Azure, Firebase, Amazon Web Services (AWS), Google Cloud

The most amazing...

...project I've had was leading a 20-person team to develop a super app for food delivery, medicine, and an online wallet.

Work Experience

Associate Manager

2020 - PRESENT
EY
  • Advised clients on the technical aspects of software development projects, ensuring alignment with business goals and industry best practices.
  • Actively involved in go-to-market initiatives, preparing knowledge documents, and performing research presentations to effectively position the company during bidding activities.
  • Led multiple mobile projects as the primary developer, fostering collaboration and innovation within cross-functional teams.
  • Developed robust software solutions across various projects, leveraging both mobile and web technologies to deliver high-quality applications.
  • Built and maintained mobile and web applications as a full-stack developer, addressing bug fixes and implementing new features to enhance user experience.
  • Engaged in all project stages, from proof of concept (POC) development and research to ongoing issue management and resolution.
  • Improved team productivity by planning development progress, optimizing branching strategies, and implementing CI/CD pipelines for efficient deployment.
Technologies: React Native, Kotlin, Android, AngularJS, Xamarin.Forms, SQL Server, Azure, .NET, Android SDK, Android, C#, Xamarin, Technical Leadership, Software Architecture, Google API, SourceTree, Retrofit 2, RxJava, React.js, Firebase, TypeScript, API Integration, Chatbot Development, UI Design, UX Development, Mobile Apps, APIs, Design, Expo, Google Play Console, Geolocation, Testing, Security, JSON, Spring Boot, Mobile App Design, MySQL, HTML5, WebView, AWS, .NET MAUI, UX Development, UI Development, Angular, App Store Development, Google Play Store, Authentication, Clean Code, IT Project Management, IT Projects, Audio, Speech to Text, Text to Speech (TTS), Architecture, Full-stack, Web Application, Biometrics, Cross-platform App Development, Cloud Deployment, Firebase Authentication, Object-oriented Programming (OOP), Linux, Image Processing, Artificial Intelligence, Machine Learning, Android, Web Development, Mobile App Design, Next.js, Progressive Web Applications (PWAs), Redux, CI/CD Pipelines, Xcode

Software Architect and Lead Developer

2013 - PRESENT
Freelance Work
  • Spearheaded all projects, overseeing technical implementations and feature design utilizing Firestore, MySQL, and various other back-end technologies.
  • Collaborated with stakeholders and clients throughout the entire project lifecycle, from ideation and research to design, development, launch, and ongoing maintenance.
  • Developed applications from scratch, adhering to established methodologies for software development for both corporate and public use.
  • Researched and applied various development paradigms as case studies, selecting optimal approaches tailored to specific project niches.
  • Leveraged cutting-edge technologies for features like location services, maps, payments, user experience, analytics, and behavioral patterns.
  • Led teams, established project deadlines, and collaborated effectively with team members across multiple projects.
  • Utilized tools such as Google Sheets, Docs, Slides, Trello, Jira, and DevOps to ensure teams remained organized and on track.
  • Maintained direct and timely communication with clients to address concerns and ensure project alignment with their goals.
Technologies: Android, Technical Leadership, Android SDK, Kotlin, Android, C#, GraphQL, Software Architecture, Google API, Firebase Realtime Database, SourceTree, Retrofit 2, RxJava, Firestore, Xamarin, React.js, React Native, Node.js, TypeScript, API Integration, UI Design, UX Development, Mobile Apps, APIs, Design, Google Play Console, Geolocation, Stripe Development, Testing, Security, JSON, Mobile App Design, HTML5, WebView, Algolia, UX Development, UI Development, App Store Development, Google Play Store, Authentication, React Native Navigation, Clean Code, IT Project Management, IT Projects, Speech to Text, Text to Speech (TTS), Architecture, Full-stack, Web Application, Biometrics, Cross-platform App Development, Firebase Authentication, Object-oriented Programming (OOP), Image Processing, Android, Web Development, Mobile App Design, Progressive Web Applications (PWAs), Redux, CI/CD Pipelines, Xcode

Hybrid Mobile Insurance Application Developer

2021 - 2024
Orion180 Insurance Services LLC
  • Led the development of a hybrid mobile app using Xamarin, later transitioning to .NET MAUI, enabling company agents to create contracts remotely and enhancing operational efficiency.
  • Integrated features from the existing web app by utilizing the same back-end infrastructure, ensuring a seamless user experience and data consistency.
  • Developed dynamic forms as the app’s central feature, creating 15 distinct field components that adapt based on insurance products and server responses, optimizing user input.
  • Implemented user interface designs using Xamarin Forms and .NET MAUI, customizing controls and views to meet specific platform requirements and enhance usability.
  • Expanded app functionality by creating tailored interfaces for customers, marketing personnel, and leadership, providing comprehensive analytics and insights.
  • Maintained the application by resolving bugs, implementing necessary adjustments, and incorporating new features in response to evolving business requirements and operational continuity.
Technologies: Xamarin, .NET, C#, JavaScript, HTML, CSS, Database, Mobile UI Design, Full-stack, SQL, Azure, Bootstrap, Vue.js, REST API, SourceTree, API Integration, UI Design, UX Development, Mobile Apps, APIs, Design, .NET MAUI, Google Play Console, Testing, Security, JSON, Mobile App Design, WebView, UX Development, UI Development, App Store Development, Google Play Store, Authentication, Clean Code, IT Projects, Architecture, Biometrics, Cross-platform App Development, Object-oriented Programming (OOP), Android, Mobile App Design, CI/CD Pipelines, Xcode

Mobile Developer

2022 - 2023
10 Gears LLC
  • Implemented a new server instance with automated publishing of the back-end server from a GitHub Action.
  • Managed Android and iOS mobile apps and admin web app code repositories for new feature implementations.
  • Led and integrated new database instances for the revamped back end.
Technologies: iOS, Mobile App Design, Android, Swift, Java, Kotlin, Android SDK, iOS, React.js, Express.js, Node.js, GitHub, API Integration, Mobile Apps, Google Play Console, Geolocation, Testing, JSON, Mobile App Design, App Store Development, Google Play Store, Authentication, Clean Code, Architecture, Object-oriented Programming (OOP), Android, Web Development, Mobile App Design, Xcode

Senior Native (Apple and Android) Developer

2022 - 2022
Imagemakers Inc.
  • Used Jira software for tracking tickets and maintaining applications by fixing bugs, adjusting behaviors, and fixing layouts.
  • Utilized JavaScript in analyzing and mitigating bugs on the web app.
  • Monitored the application performance, adjusting variables and logic as necessary.
Technologies: Android, iOS, Swift, Java, JavaScript, PostgreSQL, jQuery, Vanilla JS, Google API, SourceTree, API Integration, Mobile Apps, Google Play Console, Testing, JSON, Mobile App Design, App Store Development, Google Play Store, Authentication, Clean Code, Object-oriented Programming (OOP), Android, Web Development, Mobile App Design, Xcode

Senior Mobile Developer

2018 - 2020
Navitaire Philippines, Inc. (via NTT Data Philippines)
  • Maintained and enhanced existing airline applications for customers, utilizing Xamarin Forms to ensure optimal performance and user satisfaction.
  • Diagnosed and fixed bugs across both Android and iOS platforms using C#, ensuring seamless functionality and user experience.
  • Developed new features by integrating RESTful services with Xamarin Forms and C#, enhancing the capabilities of customer-facing and operational applications focused on airline operations.
  • Collaborated effectively with various departments, including QA, Business Analysis, and stakeholders, to ensure alignment on project goals and timely delivery of high-quality software.
  • Created and maintained comprehensive technical documentation for application features, enhancing team knowledge and facilitating onboarding for new developers.
  • Conducted performance assessments and optimizations of mobile applications, leading to improved load times and user engagement metrics.
  • Engaged with users and stakeholders to gather feedback, translating their needs into actionable development tasks and ensuring the applications meet business requirements.
  • Provided guidance and mentorship to junior developers, fostering skill development and promoting best practices in mobile development.
Technologies: GraphQL, Android, C#, Xamarin, Android SDK, Kotlin, Xamarin.Forms, Technical Leadership, Software Architecture, Google API, SourceTree, API Integration, Mobile Apps, Google Play Console, Geolocation, Testing, JSON, Mobile App Design, App Store Development, Google Play Store, Authentication, Clean Code, Object-oriented Programming (OOP), Android, Mobile App Design, Xcode

Senior Android Developer

2016 - 2018
Inovotek Apps, Inc.
  • Led the Android team in the implementation of new features to existing projects.
  • Maintained existing projects, including handling release and bug monitoring.
  • Discussed and implemented the architecture foundations for projects with iOS, web, and design team leaders.
Technologies: Crashlytics, Jira, Bitbucket, Technical Leadership, Android, Java, Android SDK, Kotlin, Android, Software Architecture, Google API, Firebase Realtime Database, SourceTree, Retrofit 2, RxJava, Firestore, API Integration, Mobile Apps, Google Play Console, Geolocation, Stripe Development, Testing, JSON, Mobile App Design, App Store Development, Google Play Store, Authentication, Clean Code, Object-oriented Programming (OOP), Android, Mobile App Design

Senior Android Developer

2016 - 2016
Samsung Mobile R&D Philippines
  • Spearheaded the Espresso implementation in projects.
  • Maintained existing applications by fixing bugs, adjustments, and aesthetics.
  • Implemented new features such as email automation on mobile apps and recognition of content.
Technologies: Jira, GitHub, Spoon Testing, Espresso, Eclipse, Xamarin, Android, Java, Android SDK, Software Architecture, SourceTree, RxJava, API Integration, Mobile Apps, Google Play Console, Testing, JSON, Mobile App Design, App Store Development, Google Play Store, Authentication, Clean Code, Object-oriented Programming (OOP), Android, Mobile App Design

Software Developer

2013 - 2016
KLab Cyscorpions, Inc.
  • Developed new features on existing apps. Maintained applications by adding new modules on existing features and/or creating a new module from scratch.
  • Resolved app issues by utilizing issue-tracking technologies.
  • Code-reviewed pull requests to maintain the quality of code.
  • Pioneered the usage and development of a unit testing framework using Robotium.
  • Supported, taught, and led junior developers with multiple tasks.
  • Helped with improvement and implementation of the current workflow.
Technologies: Spoon Testing, GitHub, Robotium, Eclipse, Android, Java, Android SDK, Software Architecture, Firebase Realtime Database, SourceTree, Retrofit 2, RxJava, API Integration, Mobile Apps, Google Play Console, Testing, JSON, Mobile App Design, App Store Development, Google Play Store, Authentication, Clean Code, Object-oriented Programming (OOP), Android, Mobile App Design

Basketball League Application

A React Native-based application that aims to make the organization and completion of leagues between teams with small to medium followings in neighborhoods easier and more secure. Features include the creation of leagues with maps, location setting, player selection, contract creation and bet holding and assistance, and team management.

Vehicle Dealership Management App

A React Native application that is based on an existing web application used to manage the inventory and business of dealerships across the US. Features include VIN code scanning and OCR, inventory management, listing management, and more

NFTApp

An app focusing on delivering analytics on NFTs based on different sources such as Icy.tools, NFTPort, and others. I collected data and created an attractive UI for displaying data on charts and bar charts. I also provided predictions for proper NFT staking, buying, and selling.

Guapp

A delivery platform where users can order from markets, restaurants, pharmacies, and other store categories. It utilizes Google Maps for location features and has an intuitive design that appeals to the younger market.

I have led the software development team in this project, managing at most 10 people comprised of Android, iOS, and web developers, as well as QA engineers and business analysts. We have used Firebase for the authentication, database, hosting, and analytics. We have also used Stripe for the payments.

I have also led the development of the Android app utilizing Kotlin. I have used the MVVMC architecture using Conductor for the controller and navigation stack, Dagger for dependency injection, Kotlin Coroutines for multi-threading, and Android architecture components such as ViewModel and LiveData.

Tarjemle | Translation Services

I led the development of this platform for translators. With agile practices already in place, I planned the architecture and development schedule of multiple web portals and Android and iOS applications, as well as landing pages and back-end servers.

I also personally developed the Android application for customers and translators here, wherein they can have documents analyzed and have words automatically counted.

Translators can accept and decline tasks. Both the customers and translators can coordinate with account managers for the tasks and results through the chat module (that we developed). We used Firebase Firestore for the applications' back end.

Pulire | Shoe Cleaning Service

Pulire is a service to have all kinds of shoes cleaned. It has a menu for the services you can avail of and where you'd like the shoes picked up and delivered. It has a partner app for its couriers, which I also developed. I collaborated with a team I have handpicked to create a working, commercial system complete with an admin portal.

The customer can create an order to upload pictures of a pair of shoes that need servicing and the specific services he wants. After the shop's couriers are notified and accept the pickup request, the app gives them the customer's location. The couriers then collect the items and payments. Once the shoes have arrived at the store, an admin monitors the cleaning process, prompts user updates, and users get notified through push notification. After the service is completed, the shoes will be delivered back to the customer.

PharmacyDirect | A Medicine Delivery System

https://goo.gl/xw44jc
With one of my developer friends, we created a suite of applications for a company that delivers medicine to people in South Africa.

I created the client and the delivery personnel applications.

The client application allows users to upload prescriptions and update them about concerning their deliveries, which are automatically managed by the system. It also shows them the current location of the personnel that is delivering the medicine.

For the delivery personnel app, it was designed to give the users notifications when a delivery is assigned to them as well as show the location of the client.

BaryaCard | Financial App

This app is a financial app that aims to help Filipinos save money when buying from convenience stores, food stands, etc. Instead of getting the coin change right then and there, they can choose to have it deposited into their BaryaCard account. Currently, two companies have partnered with BaryaCard so that they can offer the services within the app and be part of the profit-sharing model that my clients have envisioned.

AMPC — https://play.google.com/store/apps/details?id=com.baryacard.ampc&hl=en

Mister Donut — https://play.google.com/store/apps/details?id=com.baryacard.misterdonut&hl=en

InkMyPapers | Assignment Help

InkMyPapers is a service where students can ask for help on their essays, dissertations or presentations. I created and managed a team that will develop a multitude of apps where I developed the Android app myself.

Shawer App | eLaw App

Shawer is an eLaw application that connects lawyers with potential clients. It is an online legal services marketplace connecting consumers and lawyers across the region. Shawer app is not a law firm in of itself and doesn’t provide any legal services; it merely facilitates the connection of lawyers and clients.

Shawer users can purchase in-app currency via the Google Play and the Apple App Store and after purchase can access the available services of various lawyers and services ranging from consultations to legal representation in court.

DURA LEX | Social Italian and European Law Application

DURA LEX is a new kind of application that aims to bring social functions to a repository of Italian and European laws. It will also have powerful searching capabilities that enable users to search for resolutions and judgments to legal court cases. Currently, it is in development.

Appily | A Journal App with a Personality Analysis

I developed a journal app that has an automatic data synchronization with the back end, a Google Drive backup, a personality analysis, and a customized feedback logic. It was also implemented with Material Design so that it is compatible up to API 15.

Paloma Forum App

This project allows employees of an existing company to communicate and share information through a mobile app. The user can enter posts, categorize, send files, and collaborate on forum postings and edit material.

MyWapBlog.com

This is a blogging app that I made for an existing blogging platform. All the designs were made by the designer and I implemented them pixel by pixel. Aside from the features shown in the video, it also has push notifications for news, reminders, and more.

GetHabal

The app functions like Uber but caters to motorcycle drivers in the Philippines. The app shows the location, creates routes and maps, and lets users see the estimated arrival time and duration to gauge travel properly. The app allows drivers to receive bookings and track their history of travel.
2009 - 2013

Bachelor's Degree in Computer Science

Technological University of the Philippines - Manila, Philippines

Libraries/APIs

Node.js, Android Support Library, Retrofit 2, RxJava, Google API, X (formerly Twitter) SDK, Facebook SDK, React.js, REST API, Stripe Development, Google Maps Development, jQuery, Vue.js

Tools

Bitbucket, SourceTree, Android, Android Jetpack, Expo, WebView, Firebase Authentication, Android, Xcode, Jira, Crashlytics, Visual Studio Development, GitHub

Languages

TypeScript, JavaScript, Kotlin, Java, C#, HTML, CSS, SQL, HTML5, GraphQL, Swift, .NET

Frameworks

React Native, AngularJS, Android SDK, .NET MAUI, Angular, Next.js, Redux, .NET, Espresso, Robotium, ORMLite, Vanilla JS, Bootstrap, iOS, Express.js, Spring Boot

Paradigms

Model View Presenter (MVP), Agile Development, UI Design, UX Development, Testing, Mobile App Design, Clean Code, Object-oriented Programming (OOP), Unit Testing, Spoon Testing

Platforms

Mobile App Design, Firebase, Android, Xamarin, Algolia, Linux, iOS, Windows Development, Eclipse, Azure, Visual Studio Development, AWS

Storage

Firebase Realtime Database, Firestore, JSON, MySQL, Cloud Deployment, SQL Server, PostgreSQL, Database, Google Cloud Development

Other

Technical Leadership, Google Material Design, Google+ Authentication, EventBus, Full-stack, API Integration, Mobile Apps, APIs, Design, Google Play Console, Geolocation, Security, UX Development, UI Development, OCR, App Store Development, Google Play Store, Authentication, React Native Navigation, IT Project Management, IT Projects, Audio, Speech to Text, Text to Speech (TTS), Architecture, Full-stack, Web Application, Biometrics, Cross-platform App Development, Crypto, Image Processing, Artificial Intelligence, Machine Learning, Web Development, Progressive Web Applications (PWAs), CI/CD Pipelines, Xamarin.Forms, Software Architecture, Mobile UI Design, Mobile App Design, Chatbot Development

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