Alexander is available for hire

Alexander Naumenko

Verified Expert in Engineering

iOS Developer

Paphos, Cyprus

Toptal member since May 17, 2022

Expertise

Algorithms Code Review Full-stack Mobile App iOS Fintech Development QR Code Development Xcode Objective-C REST API Git Coding Animation Development

Bio

Alex has been working with iOS applications since 2010. During his career, he used many existing mobile frameworks, patterns, and architectures and released many successful projects. Alex's expertise spans areas such as databases (Core Data, Realm), UI (storyboards, auto layouts, auto-resizing, SwiftUI), payments (in-app, PayPal, banks), animations (UI animations, Core Animation, Lottie), graphics (Core Graphics), networks (Alamofire, Moya), push notifications, and uploading apps to App Store.

Portfolio

TapYou

Swift 5, SwiftUI, Core Audio, Observation, Combine, RxSwift, Async/Await, UIKit...

Crossbox Lap Timing

Swift 5, Moya, Alamofire, Objective-C, Geolocation, Bluetooth Low Energy (LE)...

QRme

Audio, iOS Video, Core Image, Push Notifications, Memory Management, PhotoKit...

Experience

iOS - 16 years
Objective-C - 14 years
Xcode - 14 years
Native Mobile Apps - 12 years
Swift - 9 years
Core Data - 8 years
RealmSwift - 4 years
SwiftUI - 3 years

Preferred Environment

Xcode, Visual Studio, Cursor AI, Postman, Charles

The most amazing...

...thing I've developed is an official application for Etihad Airways.

Work Experience

Senior iOS Developer

2023 - PRESENT

TapYou

Redesigned multiple app screens, improving UI consistency, interaction patterns, and the overall user experience.
Reworked the photo and video import flow, including import algorithms, progress tracking, and database schema changes.
Improved reliability of long-running media import operations by redesigning how progress is stored and resumed.
Developed a dynamic media Dashboard similar to Apple Photos, with zoom-in and zoom-out behavior and adaptive grid density.
Extended the Dashboard into a TikTok-like vertical feed mode when the layout reaches a single-item-wide view.
Implemented video playback inside large media cells and directly within the media grid, including playback progress visualization.
Optimized chat loading at app startup by redesigning lookup and indexing logic, reducing quadratic behavior to logarithmic access patterns.
Developed a custom hang detection mechanism to identify UI freezes and improve app stability.
Reworked resource loading across the app, making it more dynamic, scalable, and easier to extend.
Used Cursor and LLM tools to introduce a spec-driven development workflow with requirements analysis, planning, staged delivery, and tests.

Technologies: Swift 5, SwiftUI, Core Audio, Observation, Combine, RxSwift, Async/Await, UIKit, Minimum Viable Product (MVP), iOS Animations, Architecture, CI/CD Pipelines, Agile, OpenAI, Mobile Architecture, AI Chatbots, Social Networks, Large-scale Projects, Prototyping, Concurrency, Data Modeling, Asynchronous Data Streams, Real-time Data, Core Location, Cursor AI, Code Review, Performance Optimization, Vibe Coding, AI Integration, Apple Push Notifications, Payments, Real-time Systems, Instagram, Large Language Models (LLMs), LLM Integration

Senior iOS Developer

2023 - 2023

Crossbox Lap Timing

Reworked the existing code and implemented a new database scheme using Realm.
Implemented pagination for sessions. Improved performance of the application.
Changed the architecture and the dataflow, refactored the existing codebase.

Technologies: Swift 5, Moya, Alamofire, Objective-C, Geolocation, Bluetooth Low Energy (LE), Algorithms, RealmSwift, UIKit, Internet of Things (IoT), Minimum Viable Product (MVP), iOS Animations, Architecture, CI/CD Pipelines, Agile, Leadership, TestFlight, Mobile Architecture, Prototyping, Concurrency, Data Modeling, Core Location, Code Review, Performance Optimization, Apple Push Notifications, Payments, Fitness

iOS Team Lead

2022 - 2023

QRme

Reviewed the code as an auditor and created a list of improvements for the project.
Started to work as an iOS team lead for the project. Improved the development process (pull requests, code reviews, CI/CD).
Conducted a lot of interviews for growing the team with Middle+/Senior iOS developers. Found a new Team Lead.

Technologies: Audio, iOS Video, Core Image, Push Notifications, Memory Management, PhotoKit, Unit Testing, QR Codes, Minimum Viable Product (MVP), iOS Animations, Architecture, CI/CD Pipelines, Agile, Leadership, Social Media, TestFlight, Mobile Architecture, Social Networks, Large-scale Projects, Prototyping, Concurrency, Data Modeling, Asynchronous Data Streams, Real-time Data, Core Location, Code Review, Performance Optimization, Apple Push Notifications

Senior iOS Developer

2022 - 2023

Triller

Implemented a voice-over functionality for users to create additional audio over an existing video and adjust the volume of every component.
Re-worked the Following/Followers modules, optimizing the flow and fixing navigation bugs.
Introduced custom back-swipe navigation globally for the project and adjusted it for all existing modules.

Technologies: Algorithms, Swift, Objective-C, iOS Video, AVFoundation, AudioUnit, AudioKit, Core Audio, UIKit, PromiseKit, iOS Native Libraries, Direct to Consumer (D2C), Cocoa Touch, API Integration, REST APIs, WebSockets, Git, Slack, Audio Streaming, REST, Amazon Web Services (AWS), Auth, Amazon Transcribe, Mobile, iMessage, Streaming, iTunes Connect, Apps, Alamofire, iPhone, Unit Testing, Minimum Viable Product (MVP), iOS Animations, Architecture, Agile, Social Media, Fintech, TestFlight, Mobile Architecture, Social Networks, Large-scale Projects, Prototyping, Concurrency, Data Modeling, Asynchronous Data Streams, Real-time Data, Core Location, Code Review, Performance Optimization, Apple Push Notifications, Payments, Real-time Systems

iOS Team Lead

2013 - 2022

GrowApp Solutions

Developed a lot of iOS and Android mobile applications for banks (Moscow bank, VTB), social networks (Teamo, Gifteka, Tabor), security systems (Delta), airlines (Etihad Airways), and mobile operators (To The Moon Mobile).
Organized iOS, Android, and QA departments and monitored their results.
Trained iOS developers, collected the materials for their education, and reviewed their results.

Technologies: iOS, Objective-C, Swift, Xcode, Visual Studio, C#.NET, ASP.NET Core, SQL, Core Data, Core Graphics, Core Audio, XCTest, Bitrise, GitHub, Firebase, SwiftUI, Swift 4, Native Mobile Apps, Swift 3, Project Management, Swift 2, UIKit, Atlassian, Jira, Algorithms, SwiftLint, ARKit, iOS SceneKit, iOS SDK, XCUITest, HTML, JavaScript, Model View ViewModel (MVVM), Video Livestreaming, LiveStream, Animation, A/B Testing, Augmented Reality (AR), SQLite, Google Cloud Platform (GCP), Couchbase, iPad, GitLab, Apple, MongoDB, User Interface (UI), User Experience (UX), Core Animation, Widgets, UI Animation, iOS API, PassKit, .NET, Mobile Wallet, Google Cloud, Google Maps API, Android, WebView, Wireless, Wireless Protocols, iOS 10+, LiDAR, Back-end Architecture, Mobile Apps, Payment APIs, Firebase Realtime Database, Payment Gateways, Scrum, Kotlin, Mobile Development, Video Streaming, iOS Native Libraries, Direct to Consumer (D2C), Cocoa Touch, Geolocation, API Integration, REST APIs, WebSockets, Flutter, Firebase Authentication, Git, Slack, REST, Auth, Mobile, iMessage, gRPC, iTunes Connect, Apps, AVFoundation, Realm, Alamofire, Apple TV, Over-the-top Content (OTT), iPhone, iOS TV, Unit Testing, CouchDB, QR Codes, Internet of Things (IoT), Minimum Viable Product (MVP), iOS Animations, Architecture, CI/CD Pipelines, Agile, Leadership, Social Media, Fintech, Mobile Banking, iCloud, CloudKit, GraphQL, Mobile Architecture, Social Networks, Large-scale Projects, Prototyping, Full-stack, Apple Pay, Concurrency, Data Modeling, Asynchronous Data Streams, Real-time Data, Core Location, Maps, React Native, Code Review, Performance Optimization, Apple Push Notifications, Full-stack Development, Payments, Real-time Systems, Back-end, Apple Watch, Speech Recognition, Speech-to-Text (STT), Text-to-Speech (TTS)

Senior iOS Developer

2020 - 2021

Snowfall

Implemented an iOS application for the company's biggest client, Etihad Airways. It is an official iOS application for the client.
Involved with two of my developers, managing them and taking part in the iOS and Android apps.
Released the app, localizing it and making it available in two languages: English and Arabic (from right to left orientation of the interface).

Technologies: Swift, iOS, Xcode, CocoaPods, Core Graphics, GitHub, Firebase, Swift 4, Native Mobile Apps, Project Management, UIKit, Atlassian, Jira, Algorithms, iOS SDK, XCUITest, Animation, GitLab, Apple, User Interface (UI), User Experience (UX), Core Animation, UI Animation, iOS API, PassKit, .NET, Mobile Wallet, WebView, iOS 10+, Back-end Architecture, Mobile Apps, Payment APIs, Firebase Realtime Database, Payment Gateways, Scrum, Mobile Development, iOS Native Libraries, Direct to Consumer (D2C), Cocoa Touch, API Integration, REST APIs, Git, REST, Auth, Mobile, iTunes Connect, Apps, Realm, Alamofire, iPhone, Unit Testing, Minimum Viable Product (MVP), iOS Animations, Architecture, Agile, Fintech, Mobile Architecture, Large-scale Projects, Prototyping, Concurrency, Data Modeling, Code Review, Apple Push Notifications

iOS Developer

2010 - 2013

OctoberSoft

Implemented a lot of iOS projects. The most interesting was the social network iClouzy. One of the most complex projects was the karaoke application, where I worked with low-level audio functions for performing the audio stream.
Trained and managed the team of iOS developers of the company.
Managed the development process for many projects, including social networks, sports applications, and geo apps.

Technologies: iOS, Objective-C, ASP.NET, C#.NET, SQL, Core Data, Core Graphics, GitHub, User Experience (UX), Firebase, Native Mobile Apps, Project Management, UIKit, Algorithms, iOS SDK, HTML, JavaScript, Video Livestreaming, LiveStream, Animation, SQLite, iPad, GitLab, Apple, User Interface (UI), Core Animation, UI Animation, iOS API, .NET, Google Maps API, WebView, iOS 10+, Back-end Architecture, Mobile Apps, Payment APIs, Payment Gateways, Scrum, Mobile Development, Video Streaming, iOS Native Libraries, Direct to Consumer (D2C), Cocoa Touch, Geolocation, API Integration, REST APIs, Firebase Authentication, Git, REST, Auth, Mobile, Streaming, iTunes Connect, Apps, Alamofire, Video Codecs, iPhone, Unit Testing, Minimum Viable Product (MVP), iOS Animations, Architecture, OpenGL, Mobile Architecture, Social Networks, Full-stack, Concurrency, Data Modeling, Core Location, GPS, Code Review, Performance Optimization, Computer Vision, Games, Gamification, Payments, Back-end

C++ Developer

2008 - 2009

SoftGrad Solutions

Implemented small pet C++ projects of the company.
Supported and implemented some features using C++ in the project KidsWatch.
Implemented basic pages using ASP.NET in project 3StepShare.

Technologies: C++, C#.NET, ASP.NET, SQL, GitHub, Algorithms, HTML, JavaScript, .NET, Back-end Architecture, API Integration, REST APIs, Video Codecs, Full-stack, Data Modeling

Experience

TapYou

https://apps.apple.com/us/app/tapyou/id1505205419

TapYou is a private media-sharing and video messaging platform that helps families and close groups collect photos and videos into shared channels and turn everyday moments into collaborative memories. The product solves a common consumer problem: personal media is usually scattered across different phones, chats, and cloud libraries, making it hard to organize, revisit, and enjoy together.

Unlike public social networks, TapYou focuses on private circles, long-term memory storage, media discovery, reactions, and smooth video playback. Users can import media, browse shared content through dynamic photo and video experiences, react to memories, and keep important moments available over time. From a business perspective, the app is focused on engagement, retention, private social interaction, and subscription-based storage value.

My work covered major redesign efforts, photo/video import reliability, dynamic media browsing, grid and feed playback, startup performance optimization, app stability, AI-powered search, onboarding, and network connection diagnostics.

Triller

This is a substantial TikTok-like video social network. You can post a video, start a live-stream find, add friends, and follow celebrities. The project includes a lot of low-level audio and video handling.

To The Moon Mobile

I served as a mobile development team lead. The client's goal was to combine the functionality of the mobile operator and the finance functionality. At first, it was a cryptocurrency exchange service and later became a mobile bank client. We implemented both iOS and Android apps. After that, there were a lot of steps of refactoring and adding new functionality. Now the app is working in the UK.

Etihad Airways

https://apps.apple.com/ae/app/etihad-airways/id988860942

I led the mobile development team in creating two apps from scratch for both iOS and Android. These apps were developed with English and Arabic localization. I completed the development within a few months and provided ongoing support alongside my skilled team of developers.

UNO Mobile

https://apps.apple.com/bg/app/1mobile/id1490246867?platform=iphone

A mobile operator from Italy: we reworked the old applications' design, created the plan of optimizations for the existing back end, and implemented new mobile applications from scratch. I also set CI/CD with Bitrise, Jira automation, GitHub Actions, and Git hooks.

Full-jacket AR

https://apps.apple.com/cy/app/full-jacket/id6443995603

The application helps you share and view high-resolution artwork of your vinyl records in AR. I used SceneKit to generate AR models and shared them using the Supabase service and Apple authentication.

MoneyBase

https://apps.apple.com/app/moneybase/id1614797633

The financial application that includes managing your cards, 3D models, and different themes. I worked with MVVM models before the back end provided its API, so the main part of the UI had been implemented and tested before the back end was ready.

BusyCal

https://apps.apple.com/us/app/busycal/id1035689743

A powerful and flexible calendar app for managing busy schedules, events, and tasks. I worked with many Core Data tables for managing all events and calendars, the inner logic of which resulted in a compelling app that integrates with many calendar services.

Bringo

Bringo is a service for couriers and their customers. I implemented the iOS application for couriers and also took part in back-end development. We also integrated the service with Alfa Bank, one of the biggest Russian banks.

BaZi Hero

A Four Pillars calculator powered by a sophisticated algorithm that accurately analyzes charts, serving both beginners and professionals. We developed and maintened the in-app purchase system for this application.

Neebo

https://itunes.apple.com/us/app/neebo/id1250419822

This is a monitor for children. The application connects to the nearest available device through Bluetooth Low Energy before transmitting data to the cloud via a mobile containing the app. We used VIPER as the architecture of this app.

Perepel Karaoke

This application helps people find the song they want to sing. The graphics in OpenGL create a great vibe. Audio algorithms give users their performance results and help them sing better by using audio shifting.

Gifteka

Gifteka is a social network from the client in the USA. The idea was to create events where users can collect money for presents. The users can add the presents they want to get to their profile. The event can be secret, so the receivers don't know which surprises they are getting.

iClouzy

https://www.iclouzy.com/

iClouzy was a very nice social network. A lot of its ideas we now can see on Tinder. There was matching by geolocation, and we implemented messages, friends, matches, and some simple entertainment features. Unfortunately, it was closed because of a lack of budget.

Puxxle

A social network where you can send photos as puzzles. It included messages, friends, and audio and video messages. The network also included its own currency, puxxles. You could top up your balance using in-app purchases.

Education

2010 - 2012

Master's Degree in Information Technologies

Southern Federal University - Rostov-on-Don, Russia

2006 - 2010

Bachelor's Degree in Informatics and Applied Mathematics

Southern Federal University - Rostov-on-Don, Russia

An Online Freelance Agency

Skills

Libraries/APIs

Core Animation, iOS API, iOS Native Libraries, REST APIs, Codable, Auth, Alamofire, Core Graphics, RxSwift, Google Maps API, Instagram API, CocoaPods, Jira REST API, GitHub API, PromiseKit, AudioKit, Core Audio, Core Image, PhotoKit, Apple Subscriptions, OpenGL

Tools

Xcode, GitHub, Atlassian, Jira, Git, SwiftLint, Figma, GitLab, WebView, Moya, Firebase Authentication, iTunes Connect, TestFlight, Apple Push Notifications, Slack, Visual Studio, Amazon Transcribe, YouTrack, XML Interface Builder (XIB), Auto Layout, Postman, Charles

Languages

Objective-C, Swift, Swift 4, Swift 3, Swift 5, Delphi 7, C#.NET, SQL, Swift 2, HTML, JavaScript, Kotlin, GraphQL, C++, Java, Pascal

Frameworks

XCTest, iOS SDK, XCUITest, SwiftUI, UIKit, .NET, Cocoa Touch, Core Location, RealmSwift, Core Data, iOS SceneKit, ARKit, PassKit, gRPC, CloudKit, ASP.NET, ASP.NET Core, AudioUnit, Flutter, Combine, Metal, React Native, Core ML

Paradigms

Mobile Development, Model View ViewModel (MVVM), Back-end Architecture, Scrum, REST, Agile, Unit Testing, Real-time Systems, VIPER Architecture, Testing, Model View Presenter (MVP), Gamification

Platforms

iOS, Firebase, Apple, Android, iOS 10+, Mobile, Google Cloud Platform (GCP), Amazon Web Services (AWS), iCloud, Apple Watch, Bitrise, Bluetooth Low Energy (LE), Apple TV

Industry Expertise

Project Management, Social Media

Storage

SQLite, NoSQL, Google Cloud, Firebase Realtime Database, Realm, Couchbase, MongoDB, CouchDB, PostgreSQL, Databases, API Databases, JSON

Other

Mobile App Development, Native Mobile Apps, Algorithms, Mobile Apps, Animation, APIs, iPad, User Interface (UI), UI Animation, Proof of Concept (POC), AVFoundation, Payment APIs, Payment Gateways, Video Streaming, Direct to Consumer (D2C), Geolocation, API Integration, Audio Streaming, iMessage, Apps, iPhone, QR Codes, Minimum Viable Product (MVP), iOS Animations, Architecture, Leadership, Fintech, Mobile Banking, Mobile Architecture, Social Networks, Prototyping, Full-stack, Concurrency, Data Modeling, GPS, Maps, Cursor AI, Code Review, Performance Optimization, Payments, Video Livestreaming, LiveStream, A/B Testing, Augmented Reality (AR), User Experience (UX), Widgets, Mobile Wallet, Wireless, Wireless Protocols, WebSockets, Streaming, Internet of Things (IoT), CI/CD Pipelines, AI Chatbots, Artificial Intelligence (AI), Apple Pencil, Large-scale Projects, Apple Pay, Asynchronous Data Streams, Real-time Data, Audio Processing, Computational Mathematics, Games, Vibe Coding, AI Integration, Full-stack Development, Back-end, Instagram, Fitness, Large Language Models (LLMs), Speech Recognition, LLM Integration, Speech-to-Text (STT), Text-to-Speech (TTS), 3D Animation, Audio, iOS Video, LiDAR, In-app Purchases, Google In-app Billing, Video Codecs, Over-the-top Content (OTT), iOS TV, Push Notifications, Memory Management, Hard Coding, Coding, Complex Problem Solving, Delegates, Observation, Async/Await, Tables, Networking, Data, Subscriptions, Programming, Functions, Structure, Version Control, App UI, OpenAI, GCD, Multithreading, Coordinator Pattern, MVVM-C, Storyboarding, Machine Learning, Computer Vision

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Work Experience

Senior iOS Developer

2023 - PRESENT

TapYou

Redesigned multiple app screens, improving UI consistency, interaction patterns, and the overall user experience.
Reworked the photo and video import flow, including import algorithms, progress tracking, and database schema changes.
Improved reliability of long-running media import operations by redesigning how progress is stored and resumed.
Developed a dynamic media Dashboard similar to Apple Photos, with zoom-in and zoom-out behavior and adaptive grid density.
Extended the Dashboard into a TikTok-like vertical feed mode when the layout reaches a single-item-wide view.
Implemented video playback inside large media cells and directly within the media grid, including playback progress visualization.
Optimized chat loading at app startup by redesigning lookup and indexing logic, reducing quadratic behavior to logarithmic access patterns.
Developed a custom hang detection mechanism to identify UI freezes and improve app stability.
Reworked resource loading across the app, making it more dynamic, scalable, and easier to extend.
Used Cursor and LLM tools to introduce a spec-driven development workflow with requirements analysis, planning, staged delivery, and tests.

Senior iOS Developer

2023 - 2023

Crossbox Lap Timing

Reworked the existing code and implemented a new database scheme using Realm.
Implemented pagination for sessions. Improved performance of the application.
Changed the architecture and the dataflow, refactored the existing codebase.

iOS Team Lead

2022 - 2023

QRme

Reviewed the code as an auditor and created a list of improvements for the project.
Started to work as an iOS team lead for the project. Improved the development process (pull requests, code reviews, CI/CD).
Conducted a lot of interviews for growing the team with Middle+/Senior iOS developers. Found a new Team Lead.

Senior iOS Developer

2022 - 2023

Triller

Implemented a voice-over functionality for users to create additional audio over an existing video and adjust the volume of every component.
Re-worked the Following/Followers modules, optimizing the flow and fixing navigation bugs.
Introduced custom back-swipe navigation globally for the project and adjusted it for all existing modules.

iOS Team Lead

2013 - 2022

GrowApp Solutions

Developed a lot of iOS and Android mobile applications for banks (Moscow bank, VTB), social networks (Teamo, Gifteka, Tabor), security systems (Delta), airlines (Etihad Airways), and mobile operators (To The Moon Mobile).
Organized iOS, Android, and QA departments and monitored their results.
Trained iOS developers, collected the materials for their education, and reviewed their results.

Senior iOS Developer

2020 - 2021

Snowfall

Implemented an iOS application for the company's biggest client, Etihad Airways. It is an official iOS application for the client.
Involved with two of my developers, managing them and taking part in the iOS and Android apps.
Released the app, localizing it and making it available in two languages: English and Arabic (from right to left orientation of the interface).

iOS Developer

2010 - 2013

OctoberSoft

Implemented a lot of iOS projects. The most interesting was the social network iClouzy. One of the most complex projects was the karaoke application, where I worked with low-level audio functions for performing the audio stream.
Trained and managed the team of iOS developers of the company.
Managed the development process for many projects, including social networks, sports applications, and geo apps.

C++ Developer

2008 - 2009

SoftGrad Solutions

Implemented small pet C++ projects of the company.
Supported and implemented some features using C++ in the project KidsWatch.
Implemented basic pages using ASP.NET in project 3StepShare.

Technologies: C++, C#.NET, ASP.NET, SQL, GitHub, Algorithms, HTML, JavaScript, .NET, Back-end Architecture, API Integration, REST APIs, Video Codecs, Full-stack, Data Modeling

Experience

TapYou

https://apps.apple.com/us/app/tapyou/id1505205419

Triller

To The Moon Mobile

Bringo

BaZi Hero

Neebo

https://itunes.apple.com/us/app/neebo/id1250419822

Perepel Karaoke

Gifteka

iClouzy

https://www.iclouzy.com/

Puxxle

Education

2010 - 2012

Master's Degree in Information Technologies

Southern Federal University - Rostov-on-Don, Russia

2006 - 2010

Bachelor's Degree in Informatics and Applied Mathematics

Southern Federal University - Rostov-on-Don, Russia

An Online Freelance Agency

Skills

Libraries/APIs

Tools

Languages

Objective-C, Swift, Swift 4, Swift 3, Swift 5, Delphi 7, C#.NET, SQL, Swift 2, HTML, JavaScript, Kotlin, GraphQL, C++, Java, Pascal

Frameworks

Paradigms

Mobile Development, Model View ViewModel (MVVM), Back-end Architecture, Scrum, REST, Agile, Unit Testing, Real-time Systems, VIPER Architecture, Testing, Model View Presenter (MVP), Gamification

Platforms

iOS, Firebase, Apple, Android, iOS 10+, Mobile, Google Cloud Platform (GCP), Amazon Web Services (AWS), iCloud, Apple Watch, Bitrise, Bluetooth Low Energy (LE), Apple TV

Industry Expertise

Project Management, Social Media

Storage

SQLite, NoSQL, Google Cloud, Firebase Realtime Database, Realm, Couchbase, MongoDB, CouchDB, PostgreSQL, Databases, API Databases, JSON