
Azzaro Mujic
Verified Expert in Engineering
iOS Developer
Zagreb, Croatia
Toptal member since February 25, 2019
Azzaro is an experienced software engineer with a decade of expertise in product-oriented development. He excels in crafting innovative native iOS and Android apps and aligns business objectives with technology to maximize impact. He is skilled in leadership, programming, algorithms, cost estimations, process optimization, code review/testing, architectural design, issue resolution, strategic planning, client management, quality assurance, and project management. He delivers exceptional value.
Portfolio
Experience
- Objective-C - 10 years
- iOS - 10 years
- Swift - 10 years
- iOS Animations - 9 years
- Code Architecture - 6 years
- Team Leadership - 4 years
- Agile Software Development - 4 years
- Scrum Master - 3 years
Preferred Environment
Charles, Zeplin, Sketch, Xcode, Git, MacOS, CTO
The most amazing...
...thing I’ve done was build a dream team—highly motivated and satisfied—where the client ended up happy and all of the deadlines were met.
Work Experience
Senior iOS Developer
Reddit, Inc.
- Built user-facing moderation features powered by AI-assisted content classification, enabling faster detection and handling of rule-breaking posts, which significantly accelerated moderation response times and improved community health.
- Wrote comprehensive unit and snapshot tests with over 80% coverage, improving code reliability, reducing regressions, and supporting faster, safer feature delivery across multiple product teams.
- Collaborated with cross-functional teams—including product, design, and back end—to deliver high-impact moderation tools, aligning technical implementation with user needs and ensuring a cohesive end-to-end experience.
Senior iOS Developer
DAZN
- Led the development of a multi-platform streaming app for iPhone, iPad, and Mac using SwiftUI and Combine, delivering a consistent and high-performance experience across all Apple devices.
- Implemented watch party and live streaming features, enhancing social engagement and real-time interaction for users across global sports events.
- Established a robust testing framework incorporating unit, snapshot, and Gherkin-based UI tests, significantly improving code quality and reducing bugs in production.
Swift Developer
The Weather Group - Main
- Built and maintained core video streaming features for live and on-demand content, ensuring consistent performance across 200+ local news, weather, and entertainment channels.
- Collaborated with product, back-end, and QA teams to launch real-time updates for hyperlocal content delivery, including breaking news and severe weather alerts tailored to user location.
- Implemented ad monetization features within live and on-demand video streams, enabling seamless mid-roll ad insertion during TV shows and movies without disrupting playback or user engagement.
iOS Engineer
Koala Labs, Inc.
- Led the development of a scalable white-label food ordering platform using MVVM and Coordinator architecture and RxSwift, enabling rapid onboarding of major U.S. brands like Mod Pizza, Capriotti’s, and Waba Grill.
- Implemented real-time order tracking and push notification flows, delivering a seamless and intuitive user experience that improved customer engagement and reduced support inquiries.
- Ensured high code quality and stability through comprehensive unit and snapshot testing, while integrating secure online payment functionality to support safe and frictionless transactions.
Freelance Lead Senior iOS Developer
Sumeru Software Solutions Pvt Ltd
- Developed real-time communication using VoIP, including audio and video streaming.
- Worked on a messenger feature with more than one million users. Used the Realm database to store messages.
- Implemented SSO for a mobile app so that the app can authenticate into multiple external web pages.
- Implemented webhooks so the app can pay instead of using an external web.
- Coached and reviewed the performance of the engineering team.
- Led the iOS team with a focus on architecture and clean code.
Head of Mobile Development | Team leader | Senior iOS Developer
Undabot
- Supervised efficient workflows within the company and ensured compliance with company policies and regulations.
- Designed strategic plans to provide effective product development.
- Ensured appropriate implementation of all methodologies and development processes.
- Facilitated interviews to hire appropriate employees and provided training to achieve all organizational goals.
- Coordinated with the R&D department and prepared plans for effectively integrating various technical skills.
- Led a mobile department with more than 20 people to achieve the highest technical goals.
- Led a 10+ member team and drove collaboration.
- Organized meetings and scrums for seamless communication.
- Played a key role in recruiting new staff and building a strong team.
- Improved the business and development processes inside the company.
iOS Developer
Infinum
- Built multiple iOS apps with an emphasis on good UI/UX.
- Developed various iOS apps written in Swift and Objective-C using MVC, MVVM, or VIPER architecture.
- Meticulously crafted a bespoke user interface (UI) that exudes attention to detail. Every aspect, from the layout to the animations, has been thoughtfully designed to ensure a seamless and engaging user experience.
- Defined and implemented an offline mode for the app.
- Wrote unit and UI tests to ensure the stability of the written code.
- Performed routine code reviews to ensure code quality and facilitate collaboration.
Experience
Reddit | Large Social Network
DAZN | Live and On-demand Sports Streaming
White-label Food Ordering App
https://chowly.com/Working closely with our client based in New York, we integrated famous food brands such as Mod Pizza, Capriotti's, and Waba Grill into the app. Users could easily browse menus, customize orders, and place food orders from their favorite restaurants within the app.
The Koala app provided a seamless and intuitive user experience, allowing customers to track their orders in real-time and receive timely notifications. The app also facilitated secure online payments, ensuring a convenient and safe transaction process.
Adopting modern development practices and technologies, we delivered a high-quality white-label food ordering app tailored to our client's requirements.
Njuskalo
https://www.njuskalo.hr/With the Njuskalo application, you can:
• Submit and manage ads
• Search and browse ads
• Save interesting ads
• Save queries with filters
• Modify user data
• Pay funds on balance (card, PayPal, Paysafe, SMS)
• View accounts and traffic
• Push ads to the top of the list using the "Jump to Top" feature
My initial role in this project was as an iOS developer, and I became the team leader and scrum master after one year.
We Vibe App
https://apps.apple.com/us/app/we-vibe-app/id890526071Elyments | Social Media Simplified
https://www.elyments.com/The app is written in Swift using MVVM architecture with Coordinator.
My role was to improve architecture, educate others, improve processes, and make things work.
A1 Telecom
https://play.google.com/store/apps/details?id=by.a1.selfcare&hl=hr• Monitor balance and optimize costs
• Top-up and pay on the go
• Manage services and update packages
• Control the rest of the traffic, minutes, and SMS
• View accruals for the current period
• Enable or disable additional services
• Change the tariff plan
• Top-up with A1 banking
• Find your nearest A1 office
• Find out about A1's best deals first
Aircash | Mobile Money Transfer App
https://aircash.eu/The iOS app is written in Swift. It uses the MVVM architecture pattern and a reactive approach (RxSwift).
Unit tests are written using Quick/Nimble frameworks. In addition to the unit, the app also has a suite of snapshot tests.
The app is hosted on a GitLab repository and uses GitLab integrated CI and CD features.
Takko | Video-sharing App
Taskkey
The app is written in Swift using MVVM architecture. The back end is written in Firebase; all data is encrypted.
My role was to improve architecture, educate others, improve processes, and push the app to the App Store before a hard deadline.
FOREO For You
https://apps.apple.com/us/app/foreo-for-you/id1362085228Features allowed users to:
• Connect and manage FOREO skincare devices via Bluetooth
• Receive tutorial treatments on the phone
• Shop within the app
Trucker
The app is written in Swift using VIPER architecture and clean code. The code is tested using unit tests (Quick and Nimble) and UI tests.
The app includes amazing custom animations and transitions.
Meddox Healthcare Mobile App
https://apps.apple.com/us/app/meddox/id1617082886Meddox featured an impressive AI-powered photo recognition capability, enabling users to scan and digitize their medical records effortlessly. The app securely stored the recognized data alongside the original images.
Additionally, Meddox included a calendar feature to help users manage medical appointments and medications. With a focus on data security, I implemented robust measures such as encryption and secure authentication.
Collaborating with designers, I ensured a seamless user interface and experience. Leading the development process and meeting deadlines, I facilitated an efficient workflow. In summary, I successfully led the team in creating Meddox, a healthcare app that securely stores medical records, and leverages AI for photo recognition, integrates a calendar, and prioritizes user privacy.
OASC Academic Skills Training | Educational Mobile App
https://dantes.petersons.com/The app is written in Swift. It uses the MVVM architecture pattern and a reactive approach (RxSwift). It has an offline mode implemented with core data. It uses the JSON:API standard for communication with the back end.
I led a team of two. We aimed to write clean, testable code and deliver a great UI/UX product. I had daily meetings where we communicated with the back-end team, a designer, the Android team, and the client.
Alias Words
Pasta Maestro
The app is written in Objective-C using VIPER architecture.
I aimed to build an iOS app for iPhone and iPad that supports portrait and landscape orientation. The app also includes an offline mode built with the Core Data framework. I have worked in a team of two.
iVictim
https://github.com/amujic5/iVictimIt includes:
- Bad login
- Piracy detection
- Jailbreak detection
- Screenshot vulnerability
- Pasteboard vulnerability
- SSL pinning
- Transport layer security
- Web view vulnerability
- Brute force
- Local storage vulnerability
Blog Post: So You Think You Can Call Yourself a “Senior iOS Developer”?
Blog Post: Animations as a Part of Your Daily Job
However, it is not enough to only have a good design in your applications for the perfect UX/UI. Nowadays we have to take one step forward and make animations a part of UX/UI. In my opinion, every mobile application should contain animations.
Blog Post: Getting Deeper With Deep Linking on iOS
Education
Master's Degree in Computer Science
University of Zagreb, Faculty of Electrical Engineering and Computing - Zagreb, Croatia
Bachelor's Degree in Computer Science
University of Zagreb, Faculty of Electrical Engineering and Computing - Zagreb, Croatia
Certifications
Scrum Master
Scrum Alliance
Skills
Libraries/APIs
Social Media APIs, JSON API, Core Animation, CocoaPods, RxSwift, Google Maps SDK, Lottie-iOS, REST APIs, Twilio API, Xcode Server, Facebook iOS SDK, Parse SDK, Camera API, WebRTC, Google API, Firebase iOS SDK, Apple Maps API, JSONAPI::Resources, Google Maps, SnapKit, Pushwoosh, RxCocoa
Tools
Auto Layout, Xcode, Git, GitHub, GitLab, GitLab CI/CD, AsyncDisplayKit, Charles, Charles Proxy, SourceTree, Fastlane, Figma, PaintCode, Sketch, Zeplin, Optimizely, Jira, CircleCI, Bazel
Languages
Swift, Objective-C, Kotlin, C++, Swift 3, Java, SQL, HTML, PHP
Frameworks
Core Data, UIKit, Viper, iOS Frameworks, SwiftUI, RealmSwift, ARKit, Core ML, iOS SceneKit, OAuth 2, Core Motion, Vapor, iOS SDK, Core Bluetooth, Combine, Metal, StoreKit
Paradigms
Model View Presenter (MVP), API Architecture, Agile Software Development, Model View ViewModel (MVVM), Mobile Development, Waterfall Development, REST, Unit Testing, VIPER Architecture, HIPAA Compliance, Agile, Scrum, Clean Architecture, Clean Code
Platforms
iOS, Firebase, Twilio, Android, Parse, Apple TV, Apple Watch, MacOS, tvOS
Storage
Firebase Realtime Database, Realm, JSON, SQLite, PostgreSQL
Industry Expertise
Social Media, Project Management
Other
Video Streaming, Code Architecture, CI/CD Pipelines, Social Media Apps, Social Media Login, Mobile UI, Mobile UX, Mobile Video, Architecture, iOS Design Guidelines, Leadership, Mobile Security, Team Leadership, iOS Animations, Bluetooth, iOS Camera, Live Chat, Lottie, Social Networks, Mobile Apps, UI Animation, APIs, Design Systems, Animation, Custom Views, calayer, Health & Wellness, AI Integration, Offline Data Synchronization, App Store, Google Play Store, Videos, Audio Streaming, Estimations, iOS App Design, iPad, Product Management, Business Analysis, Scrum Master, Certified ScrumMaster (CSM), API Documentation, Communication, Empathy, Planning, QA Automation, GitFlow, Security, Augmented Reality (AR), 3D Modeling, CTO, Artificial Intelligence (AI), Webhooks, VoIP, Real-time Communication (RTC), Crypto, 3D Secure, 3D Scanning, ML Kit, Messenger, Push Notifications, Writing & Editing, Blogging, Deep Linking, Minimum Viable Product (MVP), R&D, Machine Learning, Driving, iPhone, UX Analysis, Quality Assurance (QA), UI Testing, WebKit, Networking, Broadcasting, TV Broadcasting, Streaming, HTTP Live Streaming (HLS), Over-the-top Content (OTT), iOS Video, iOS TV, TV, Multicast, 3D Graphics, Online Payments, Consumer-facing Products
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