John Ernest Guadalupe
Verified Expert in Engineering
Android Developer
Santo Tomas, Calabarzon, Philippines
Toptal member since December 18, 2015
John is a results-driven professional with a strong focus on value. He collaborates closely with clients to develop user-friendly products that fulfill business objectives. His passion lies in bringing innovative, market-disrupting ideas to life, and he is adept at delivering business-specific solutions that meet the highest standards.
Portfolio
Experience
Availability
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 handled is a super app that has food deliveries, medicine, and an integrated online wallet feature. I led an IT team to launch the project.
Work Experience
Associate Manager
EY
- Guided clients on the technical aspects of their projects.
- Assisted teams in multiple mobile projects, being the lead developer on several projects.
- Developed software for multiple projects spanning mobile and web technologies.
- Served as a full-stack developer building mobile and web applications. I also maintained existing apps for bug fixes and new feature integration.
Software Architect and Lead Developer
Freelance Work
- Developed applications from the ground up, following the appropriate methodologies for software development for corporate and public use.
- Studied and implemented different paradigms as case studies for different projects to know the best ones for different niches.
- Utilized multiple leading technologies for features such as location, maps, payments, user experience, analytics, and behavior patterns.
- Led teams, set project deadlines, and worked as part of teams for different projects.
- Used Google Sheets, Docs, and Slides to keep teams on track.
- Communicated directly and promptly with the client about any concerns regarding the project.
- Implemented Material Design principles on different projects.
Hybrid Mobile Insurance Application Developer
Orion180 Insurance Services LLC
- Led the development of an application by integrating features from the web app using the same back-end infrastructure.
- Implemented user interface designs utilizing Xamarin Forms and .NET MAUI. Tailored controls and views to meet specific platform requirements. Adapted behaviors and interfaces for the implementation of features.
- Maintained the application by resolving bugs, making necessary adjustments, and incorporating new features as dictated by business requirements and operational continuity.
Mobile Developer
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.
Senior Native (Apple and Android) Developer
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.
Senior Mobile Developer
Navitaire Philippines, Inc. (via NTT Data Philippines)
- Maintained existing airline applications for customers developed using Xamarin Forms.
- Fixed bugs on both Android and iOS platforms using C#.
- Developed new features involving RESTful services, Xamarin Forms, and C#.
Senior Android Developer
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.
Senior Android Developer
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.
Software Developer
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.
Experience
Basketball League Application
Vehicle Dealership Management App
NFTApp
Guapp
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 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
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/xw44jcI 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
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
Shawer App | eLaw App
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
Appily | A Journal App with a Personality Analysis
Paloma Forum App
MyWapBlog.com
GetHabal
Education
Bachelor's Degree in Computer Science
Technological University of the Philippines - Manila, Philippines
Skills
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, Unit Testing, Spoon Testing
Platforms
Mobile App Design, Firebase, Android, Xamarin, Algolia, Linux, iOS, Windows Development, Eclipse, Azure Design, 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 Development, 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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