Nikola Velimirovic, Developer in Podgorica, Podgorica Municipality, Montenegro
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Nikola Velimirovic

Verified Expert  in Engineering

Software Developer

Podgorica, Podgorica Municipality, Montenegro
Toptal Member Since
May 30, 2016

Nikola is an experienced Android and Kotlin developer with over 10 years in the field and a passion for staying ahead in mobile technology. He has delivered high-quality, widely-used applications and excels in TDD and reactive and functional programming. Nikola has worked in diverse, cross-functional teams and is renowned for his excellent communication skills and ability to collaborate effectively with team members of all backgrounds and expertise.


Goldman Sachs
Android, iOS, Jetpack Compose, Mobile Applications, Dependency Injection
PCCW Vuclip Pte Ltd
Jira, Room, Firebase, Android, Kotlin, Jetpack Compose, Mobile Applications...
Crowd Mobile
Node.js, Android, Kotlin, Firebase, Mobile Applications, Dependency Injection




Preferred Environment

Kotlin, Git, Android Studio, MacOS

The most amazing...

...project I've worked on is an app called Shpock, which is used by more than 10 million users on Android alone.

Work Experience

Android Mobile Engineer

2021 - 2023
Goldman Sachs
  • Took part in the checking team as an Android developer on the Marcus application for over 2.5 years.
  • Developed an application with Kotlin, RxJava, and Jetpack as our main stack.
  • Wrote new features and fixed a bunch of old bugs while trying to maintain and increase our test coverage.
Technologies: Android, iOS, Jetpack Compose, Mobile Applications, Dependency Injection

Android Architect

2018 - 2020
PCCW Vuclip Pte Ltd
  • Worked on version two of the leading in-house project that was supposed to outperform the old version in performance and stability.
  • Developed and designed a new FSM-based framework for dispatching events, switching screens, analytics, etc.
  • Implemented a bunch of memory and performance optimizations to speed up the loading and opening of certain screens and the app in general.
  • Redid the app login options using Firebase, mainly email, and password, Facebook, Google sign-in, and OTP SMS login.
  • Added tracking of anonymous users via Firestore mechanisms.
Technologies: Jira, Room, Firebase, Android, Kotlin, Jetpack Compose, Mobile Applications, Dependency Injection

Android Developer

2018 - 2018
Crowd Mobile
  • Worked on development of Ask Bongo app as only Android developer using Kotlin.
  • Created the back-end's structure and underlying API calls using a Firebase database and Firebase Functions.
Technologies: Node.js, Android, Kotlin, Firebase, Mobile Applications, Dependency Injection

Android Developer

2016 - 2018
Vitalize LLC
  • Worked with a team of four on a number of apps, the main one being a social app called Bodyspace which has almost five million users on Android alone.
  • Developed a app that allows users to buy supplements and other fitness-related products.
  • Worked in a completely remote position, with the main office being in Boise, Idaho, USA.
Technologies: MongoDB, Firebase, Node.js, Android, Java, Kotlin, Mobile Applications, Dependency Injection

Senior Android Developer

2015 - 2016
Bitsfabrik GmbH
  • Worked as an Android and Java developer on multiple projects; some of which are in-house projects and others are for the clients.
  • Worked with in-house clients such as Samsung and Austrian-based companies.
  • Mainly developed on the in-house project which can be found at; built more than 90% of the code base.
Technologies: Java, Android, Mobile Applications, Dependency Injection

Lead Android Developer

2014 - 2015
Finderly GmbH
  • Worked as a developer on an Android application called Shpock in an agile/startup environment. Shpock shortly became featured on Google Play in Germany and Austria.
  • Refactored around 80% of the code and set up coding standards while migrating the project to Android Studio and Gradle.
  • Developed new features and added to existing ones, mainly in-app purchases, tablet redesign, drag-and-drop support, and more app specifics.
  • Made the crash rate lower than in the iOS version, a first in the application's history.
Technologies: Java, Android, Mobile Applications, Dependency Injection

Software Developer

2012 - 2014
ECS Enterprise Solutions Ltd.
  • Developed and maintained the most popular banking platform in Montenegro which was our in-house solution.
  • Wrote SQL procedures which were used for annual and monthly reporting to the Central Bank of Montenegro.
  • Worked on various projects for the company's clients.
  • Developed an in-house project called EnContent which is a platform for managing content based on JCR-283 standard.
  • Developed various Android applications.
Technologies: PostgreSQL, Microsoft SQL Server, Android, Java, Java EE, Mobile Applications, Dependency Injection

Ask Bongo

I developed an Android app used for communication with a Bongo bot. I also worked on the back-end side using Firebase.

A snippet from the store page can be found below.

Bongo is a super-intelligent monkey from the shores of Borneo, who lives to dish the dirt 24/7! Get an answer to any question anytime! Bongo knows EVERYTHING about EVERYONE! It’s super simple to use Bongo.

I worked as a lead developer on an Android application called Shpock. It is one of the most downloaded boot sale, flea market, and classifieds apps with over 10 million users.


Greetzly is the world's leading platform that allows fans to have personal video interactions with artists, athletes, and influencers of all kinds.

Lama (Let's Ask Me Anything)
Explore LAMA, the video Q&A app. Discover expert advice or share your knowledge with our growing global community. Contact inspiring people and find the answers to your business questions.


A demo application used to demonstrate the functionality of the LAMA video platform.

simpliTV Streaming
An app for streaming from an Austrian TV provider over the phone. The best part that I worked on was EPG grid ( that was scrollable both vertically and horizontally; it is visible only in tablet mode.

BodySpace is a revolutionary social fitness platform. It’s the best personal trainer combined with the world’s largest online fitness community. It’s a complete system of innovative workout tools, cutting-edge trackers, fresh content, and social features.

Jim Stoppani Shortcut to Shred

Shortcut to Shred is the ultimate fat-loss workout plan by Dr. Jim Stoppani.

Tesla Launcher

Tesla Launcher is a modern home replacement app, really extensive low-level UI project. I was involved in all stages of development.

Viu | Korean Dramas, Variety Shows, and Originals
Viu is the best drama-and-movie app for Indonesians, Malaysians, Indians, Burmese, and audiences in the Middle East, and South Africa!

You can stream and download your favorite shows, movies, TV series, and music in full HD with Viu! Watch all of this with subtitles in English, Bahasa Indonesia, Bahasa Malaysia, Burmese, Mandarin, and Arabic!

Viu gives you instant access to all your favorite dramas, comedies, horror, and more! Watch hit TV shows from Korea, Japan, China, Thailand, Indonesia, Malaysia, Myanmar, Turkey, the Middle East, and India as well as our own Viu Originals. Store
The Store app is the fastest way to shop for your favorite vitamins, supplements, and sports nutrition products. Use a wish list or the quick reorder feature to get in, get out, and get back to your workout!

Marcus by Goldman Sachs
As an Android developer with a deep understanding of the latest technologies, I had the opportunity to work as a part of the checking team for the "Marcus by Goldman Sachs" app. It was an exciting project requiring me to utilize my skills in MVVM, TDD, DI, Kotlin, and RXJAVA to ensure the app was top-notch.

My primary task was to extensively review and test the app to ensure that it met the high standards of quality and functionality expected from it. I thoroughly enjoyed identifying and resolving bugs, ensuring the app was user-friendly and performed well across multiple devices.

Overall, I found this project to be challenging and rewarding at the same time. It was a great opportunity to apply my knowledge and expertise in modern Android app development.
2009 - 2012

Bachelor's Degree in Computer Science

University of Montenegro, Faculty of Electrical Engineering - Podgorica, Montenegro


Google API, REST APIs, Android API, RxJava, Retrofit, RxJava 2, Node.js, Fabric, Twitter API, Facebook API


Gradle, MoPub, Git, Adobe Photoshop, Apache Maven, Android Studio, Jira, Asana


Android SDK, Dagger, Jersey, JUnit


Kotlin, Java, JavaScript


Design Patterns, Object-oriented Design (OOD), Object-oriented Programming (OOP), REST, Model View ViewModel (MVVM), Dependency Injection, Functional Programming, Reactive Programming, Agile Software Development


Android, Java EE, MacOS, Firebase, Tapdaq, Mixpanel, Visual Studio Code (VS Code), iOS


SQLite, MySQL, MongoDB, PostgreSQL, MSSQLCE, Microsoft SQL Server, Doctrine MongoDB ODM


Coroutines, Jetpack Compose, Mobile Applications, Room

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