Andrei Sorin Blaj, Developer in New York, United States
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Andrei Sorin Blaj

Verified Expert  in Engineering

iOS Developer

New York, United States
Toptal Member Since
October 29, 2020

Backed by a wealth of knowledge in algorithms and data structures (seven years worth), Andrei is an iOS developer with four years of experience building mobile apps for customers from all over the globe. His areas of expertise include mobile app development (iOS), video editing, various tools (Xcode, GitHub), and languages (most notably Swift). Thanks to a flexible, quick mind that's informed about the latest iOS trends, Andrei can easily adapt to new apps and design patterns for any project.


Take Off Labs
Logo Design, Terminal, Pixelmator, Firebase Analytics, Jira, Postman, Xcode...
Objective-C, Swift, iOS
S&Y Technologies LLC
iPadOS, Pixelmator, Xcode, Cloud Firestore, iOS




Preferred Environment

Terminal, Xcode

The most amazing...

...thing I've done was to record a 60-minute tutorial for a career fair on how to build an app store card transition.

Work Experience

iOS Software Engineer

2020 - PRESENT
Take Off Labs
  • Successfully built and deployed the digital scorecards feature for the Golf Genius iOS app. The product is a type of golf tournament management software used by hundreds of thousands of users worldwide.
  • Handled the monthly deployment of new features based on client requirements on Jira for the GHIN iOS app for the United States Golf Association.
  • Worked on deep links in order to seamlessly switch from one app to another in order to use a specific functionality.
  • Successfully migrated Objective-C to Swift in certain areas of the apps.
Technologies: Logo Design, Terminal, Pixelmator, Firebase Analytics, Jira, Postman, Xcode, Objective-C, Swift, iOS

iOS Software Engineer

2020 - 2020
  • Successfully migrated Swift 3 to the latest Swift version and updated the apps to support the latest iPhone screens.
  • Worked on a feature that could create and scan QR codes using the iPhone's camera, process that information, and perform different actions based on that.
  • Worked hands-on with Postman and Swagger as well as with UIkit's networking features.
Technologies: Objective-C, Swift, iOS

iOS Software Engineer

2020 - 2020
S&Y Technologies LLC
  • Created a system that could handle messaging between two users, which could be scaled to support group chats as well.
  • Successfully integrated GeoFirestore into an iOS app in order to display accurate information from Cloud Firestore based on the user's location.
  • Implemented a 2-role system made from two apps—one for the clients and one for the businesses as well as another iPad app so that restaurants could better manage their business.
Technologies: iPadOS, Pixelmator, Xcode, Cloud Firestore, iOS

iOS Software Engineer

2017 - 2019
Take Off Labs
  • Came up with the idea of remotely fetching tab bar buttons instead of having static ones and successfully deployed five apps for golfers in the United States, Australia, and other countries.
  • Integrated the Amazon Fling framework into an iOS app in order to stream content to an Amazon Fire TV directly from the user's iPhone via Bluetooth. This feature was used by hundreds of golf clubs in order to display scores on TVs for players to see.
  • Worked on and successfully deployed the score verification feature for the Golf Genius iOS app.
Technologies: Ajax, SCSS, Haml, Bootstrap, JavaScript, Logo Design, Pixelmator, Firebase, Postman, Ruby on Rails 5, Objective-C, Swift, iOS

T-Minus | Space Launch Tracker
T-Minus is one of the best space launch tracking apps on iOS.

It allows users to keep track of the upcoming launches, events, and the latest news in the space industry. From SpaceX to ULA to NASA all the information at your fingertips.

In the second version, the entire app was built programmatically in Swift and Objective-C without using CocoaPods or Storyboards. VIPER is the predominant design pattern while using transitions and animations seen in top tier apps on the App Store. Among other features, the user has the ability to change the app icon, UI appearance, filters, haptics, video quality, toggle between light and dark mode, and more.

App Store Card Transition Webinar
I was asked to record a webinar on a topic of my choice for a career fair that was to be played in front of attendees. I chose the app store card transition since it is a topic that you can't find online in an easy manner to understand or free for that matter. In the 60 minutes that I had, I implemented and explained every step necessary to improve other iOSdevelopers' appss.

With over 60,000 downloads worldwide, CineMine represents my bachelor’s thesis. Its main purpose was to simplify the amount of time it would take someone to purchase a ticket to see a movie but eventually turned into a much bigger project. Using the Movie Database API, it allows users to create accounts, follow their friends, add movies & TV shows to their watchlist, monitor every detail, and switch directly to streaming applications on your phone to start watching.

Portfolio SIite
A web version of my portfolio written in HTML, CSS, and JavaScript and deployed using GitHub Pages. Here anybody can find the latest projects that I've been working on as well as the latest version of my resume.

T-Minus Landing Page
A landing page specifically created for the T-Minus iOS app in order to promote its features and capabilities. This website is also a workaround for using another platform to create and host a privacy policy.
2016 - 2019

Bachelor's Degree in Computer Science

Babes Bolyai University - Cluj-Napoca, Romania

2012 - 2016

High School Diploma in Mathematics and Computer Science

Silvania National College - Zalau, Romania


Certificate of Completion: iOS 11 & Swift 4



Cambridge Certificate in Advanced English

University of Cambridge


Bronze Medal at the Olympiad of Informatics (National Stage)

Ministry of Education and Research Romania




Xcode, GitHub, Pixelmator, Terminal, Postman, Atom, GitHub Pages, Final Cut Pro X, Logic Pro, Jira, Firebase Analytics


Swift, Objective-C, HTML, CSS, JavaScript, HTML5, Haml, SCSS, C++


Ruby on Rails (RoR), RealmSwift, Core Data, Ruby on Rails 5, Bootstrap


iOS, Visual Studio Code (VS Code), Firebase


UI Design, UX Design


Cloud Firestore, Databases


Mobile Applications, Video Editing, Logo Design, Data Structures, Algorithms, Graphs, OOP Designs, Web Programming, System Design, Operating Systems, Geometry, Networks, Mathematics, Physics, iPadOS, Ajax

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