Petru Gabriel Lupu, iOS Developer in Arona, Spain
Petru Gabriel Lupu

iOS Developer in Arona, Spain

Member since March 19, 2015
Petru is a developer who's spent the last 14 years in the mobile industry, publishing 100+ apps in the App Store. To any project, he brings in-depth knowledge of SDKs/libraries and iOS hardware/software, exceptional OOP skills, solid Node.js knowhow, and hands-on experience with RESTful web services in mobile apps. Besides his technical expertise, he’s also comfortable with Agile workflows, working with Git, and thrives in a team environment.
Petru is now available for hire




Arona, Spain



Preferred Environment


The most amazing...

...thing I’ve developed was my personal calisthenics app. I’m personally a big fan of the field and I use it when I go to the park every day.


  • Founder

    2012 - PRESENT
    Palm Mar Studios
    • Started developing my own apps out of necessity; initially, I needed an application for my exercises in the park.
    • Aimed to build apps that make money using the guiding principle "the best app is a live app."
    • Implemented my own version of ASO (app store optimizations) on a number of apps due to a lack of resources for marketing. To offset this, I used as much as possible free stuff and what I could do myself which included promoting my apps on my own Instagram, Facebook, Pinterest, and Tumblr accounts.
    • Worked the system at Apple (which included customer support, testers, and App Store reviewers) in order to get my apps in the store as fast as possible.
    • Acted as the end-to-end creator of my apps which includes development, marketing, design, testing, delivery, and more.
    Technologies: Sketch, Adobe Photoshop, Xcode, Objective-C, Swift
  • Senior iOS Developer

    2017 - 2019
    Arnia Software
    • Created the Postbank app (iPhone and iPad) for Postbank, a major bank in Germany.
    • Developed for the Postbank project automation tests for basically every property, method, and class.
    • Worked with a big team for the Postbank project with some of them based in Germany, some in Poland, some in Romania, and many others working remotely.
    • Worked in an Agile software development.
    • Developed a demo for the Lego company in an effort to gain them as clients.
    • Built and presented a demo for MO2O in an effort to gain them as clients.
    Technologies: Xcode, Objective-C, Swift
  • Senior iOS Developer

    2017 - 2019
    • Worked on more than 15 apps for MO2O's clients including Balearia, Once, Man City, Athletic Bilbao, Telefonica, and many others.
    • Successfully held all of my meetings in Spanish for one year and later smoothly transitioned to an all English environment.
    • Quickly switched between projects; some days, working on 3-4 different projects with the result that I have no problem tackling new projects.
    • Developed both the Objective-C and Swift versions of products; sometimes creating 2-3 different Xcode versions for various projects.
    • Automated the commits using Jenkins and Slack; used Slack commands for uploading to the store or to different test servers.
    Technologies: Xcode, Objective-C, Swift
  • Senior iOS Developer

    2017 - 2018
    • Developed the iOS app (iPhone and iPad) for a major German bank called Postbank.
    • Worked with a big team with members who were based all over (Germany, Poland, Romania, and more) and had to work remotely.
    • Created automation tests for basically every property, method, and class that I implemented.
    • Worked in an Agile software development.
    • Tackled different tasks all over the app due to the project's size; it was a really interesting challenge to work on decade-old lines of code.
    Technologies: Xcode, Objective-C
  • Senior iOS Developer

    2015 - 2016
    Silver Credit
    • Developed Silver Credit, an iOS (iPhone, iPad) app that helps you find the best bank card for you. A user answers a few questions and based on the information collected, a selection of cards are suggested. You can also apply for cards through the app.
    • Successfully worked with a very demanding product owner.
    • Built up the back-end in Parse initially and then migrated it to Firebase.
    • Helped on the project with some cloud functions written in Node.js.
    • Rewrote the whole app from Objective-C to Swift.
    Technologies: Xcode, Objective-C, Swift
  • Senior iOS Developer

    2015 - 2016
    Irresistible Me
    • Built an online shop app that sold hair extensions to women from scratch with a small team consisting of a designer, a QA, a back-end developer, a PM, and an iOS developer.
    • Created various promotions often and quickly as we had to change them quite often.
    • Collaborated closely with the Adore Me team, the main competitor of Victoria's Secret in order to learn more about the industry; they helped a great deal by sharing their knowledge about online magazines.
    • Locally stored a major part of the data so the users could have access to the data really fast.
    • Implemented API calls in the background and compared the information saved locally with the information received from the server. If nothing changed, i did not do anything. If something was different, I updated the local data and refreshed the page for the user.
    Technologies: Xcode, Objective-C, Swift
  • Co-founder | iOS Developer

    2013 - 2016
    Zumzet Mobile
    • Created a number of personal apps that covered a large range of categories with a friend of mine (iOS, Android, and macOS).
    • Automated a lot of builds and changes with Fastlane.
    Technologies: Xcode, Swift, Objective-C
  • Senior iOS Developer

    2014 - 2015
    Sell It
    • Developed the iPhone and iPad version of Sell it. The company invested over 2-3 million dollars in advertising in New York in the subway and TV. The company was pretty successful and was sold to Wallapop for a lot of money and actions.
    • Worked very closely with Fabrice Grinda, one of the greatest entrepreneurs in France. He was named by Forbes the top entrepreneur in the world.
    • Worked with a large team that had members based all over different parts of the world.
    Technologies: Objective-C, iOS, Xcode
  • Senior iOS Developer

    2013 - 2015
    • Developed the iPhone and iPad version of Lofty, a marketplace for antiquities.
    • Created the iPhone version of Lofty Game.
    • Worked with one of the biggest entrepreneurs in the world, Fabrice Grinda.
    • Began my foray into working remotely.
    Technologies: Xcode, iOS, Objective-C
  • iOS Developer

    2012 - 2013
    Mobile Fun
    • Developed HOM (High on Music), an online social networking service. Users must register before using the site after which they may create a personal profile, add other users as friends, exchange messages, and receive automatic notifications when they update their profile. It's like Facebook for music.
    • Worked within a small company and really enjoyed our time together.
    • Attended numerous meetings with the founder of the company resulting in that many of our ideas were implemented in the app.
    Technologies: Objective-C, Xcode, iOS
  • J2EE Developer

    2011 - 2012
    Info World
    • Worked on the EUGEN Suite which is designed to improve the quality and management of clinical and hospital care in the areas of clinical process analysis and activity-based costing.
    • Fixed bugs, reviewed code, and investigated errors using Eclipse/Visual Studio.
    • Parsed XML using JAXB.
    • Worked with JBoss, Fiddler, and Far Manager.
    • Deployed websites on different servers.
    Technologies: Java, .NET, XML, SQL, C#
  • Team Lead Programmer

    2005 - 2011
    Advanced Mobile Applications
    • Led the US sprint team which consisted of over 12 people.
    • Organized team resources in order to deliver all the projects in time using Microsoft Project.
    • Traveled to New York, Miami, and Kansas City (United States) in order to attend different conferences regarding mobile technology.
    • Worked in New York office for more than a year.
    • Worked for a company that grew from 20 people to 200 people in less than a year.
    • Developed with Brew and Visual Studio initially before moving onto Java ME and Objective-C.
    Technologies: Objective-C, iOS, BREW, Java ME


  • Tocca (via Toptal)

    This app allows you to easily synchronize and manage all your business contacts in a secure and private way. Now you can use your phone to do the following:
    • Share your contact information with a swipe of your phone and connect with the people in real-time. Simply scan the contact information via business card, vCard, or your Tocca ID and instantly your information has been passed along.
    • Connect with contacts in your trusted extended family that are relevant to you and your needs. This feature helps you build relationships in authentic ways and truly grow your network.

  • CircleIn (via Toptal)

    This project was one of my first Toptal clients and we developed the app to help students. We used Swift 4.2 and then 5.0 to develop it using the MVVM pattern. I worked with Twilio for video communication and messages.

    Project Features:
    • Integration with Firebase
    • Push notifications were implemented with OneSignal and Firebase
    • Deep and dynamic links with
    • Analytics with Google Analytics

  • JennAir

    JennAir is the deluxe division of Whirlpool and we developed it using Rx Swift.

    I developed the framework that all the Whirlpool companies will use and first tried it out on JennAir.

    Project Features:
    • Integration with Firebase
    • Push notifications were done with OneSignal and Firebase
    • Deep and dynamic links with
    • Analytics with Google Analytics

  • Jack and Ferdi Bleisure Travel

    Jack and Ferdi is your key to unlock memorable business trips. It was created by a collective of travelers who wanted to take away more than a fridge magnet.

    I used Swift 5.0 to develop this app using the MVVM pattern.

    Project Features:
    • Integration with Firebase
    • Push notifications with OneSignal and Firebase
    • Deep and dynamic links with
    • Analytics with Google Analytics

  • Stretching and Flexibility Plans

    This is my most successful app in the App Store. It has over 100 customizable stretching exercises, over 50 predefined workout routines, and over 50 healthy recipes for meals.

    I created everything from scratch from taking photos to developing the whole app initially in Objective-C then in Swift.

    Project Features:
    • Integration with Firebase
    • Push notifications with OneSignal and Firebase
    • Deep and dynamic links with
    • Analytics with Google Analytics

  • Plank | 30-day Challenge

    Plank is a fitness app that was developed using Swift 5.0.

    Project Features:
    • Integration with Firebase
    • Push notifications with OneSignal and Firebase
    • Deep and dynamic links with
    • Analytics with Google Analytics

  • Calisthenics Workout

    This is one of my most successful apps; I initially built it with Objective-C then Swift 5.0. It also has an Apple watch app version.

    Project Features:
    • Integration with Firebase
    • Push notifications with OneSignal and Firebase
    • Deep and dynamic links with
    • Analytics with Google Analytics

  • Baby Sleep and Sounds

    I developed this app with Swift 4.2.

    Project Features:
    • Integration with Firebase
    • Push notifications with OneSignal and Firebase
    • Deep and dynamic links with
    • Analytics with Google Analytics

  • James Cookbook

    I developed this healthy meals app with Swift 5.0.

  • Postbank Finanzassistent

    I developed with Objective-C this Postbank mobile companion for your bank account. We also conducted unit testing for any class, method, or property we added, so I am very experienced with unit and E2E testing.

  • BALEÀRIA: Reserva tu viaje

    Buy and reserve tickets for boats on BALEÀRIA.

  • Jean Louis David Addict

    This app connects you to beauty salons where you can buy products and make reservations.

  • Juegos ONCE

    Juegos ONCE is an app that connects you to the national lottery in Spain. It's their companion app where you can see the numbers and more.

  • Front Office Football

    I developed this football manager game using Swift 5.0; basically it's a text-based game.

    Project Features:
    • Integration with Firebase
    • Push notifications with OneSignal and Firebase
    • Deep and dynamic links with
    • Analytics with Google Analytics

  • Photo Video Editor 4 Live Camera | Selfie Effects


  • Languages

    Swift 4, Swift 3, Swift 2, Swift 1, Swift, Objective-C, PHP, Python, Python 3, Python 2, C#, SQL, XML, Java
  • Frameworks

    iOS SDK, UIKit, .NET
  • Libraries/APIs

    iOS API, CocoaPods, Python API, Node.js, Facebook SDK, RxSwift, ReactiveX
  • Tools

    Xcode, Xcode Playgrounds, WebStorm, Sketch, GitHub, Bitbucket, GitLab, Jira, Redmine, Zeplin, Stash, Sympli, Google Analytics,, Adobe Photoshop
  • Platforms

    iOS, iOS 12, iOS 11, iOS 10+, Magento, Firebase, Java ME, BREW
  • Other

    Overlapping Development, iOS TV, iOS Video, Carthage, Embedded Software, Firebase Cloud Functions, Photoshop CC 2019, Video Chat, Mobile App Development, RESTful APIs
  • Paradigms

    RESTful Development, Dependency Injection, Model View Viewmodel (MVVM)


  • Master's Degree in Computer Science, Information Technology, and Automated Systems Science
    2000 - 2005
    The Faculty of Automatic Control and Computers | Automatica si Calculatoare - Bucharest, Romania
  • Bachelor of Science Degree in Computer Programming
    1996 - 2000
    Tudor Vianu National High School of Computer Science | Colegiul National de Informatica Tudor Vianu - Bucharest, Romania

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