Aleksandar is available for hire
Hire AleksandarAleksandar Tomislav Markovic
Verified Expert in Engineering
Software Developer
Location
Belgrade, Serbia
Toptal Member Since
January 26, 2016
Aleksandar has been a software developer for about ten years, doing everything from Assembler programming to web development and, more recently, ReactNative and React development. He has done work for companies like Sony Mobile, Goldman Sachs, Bosch, Plantronics, and Bottle Rocket Studios. His communication skills and solid development work make him avaluablel asset to any project.
Portfolio
Goldman Sachs - Main
Android, RxJava 2, Model View Intent (MVI)
MediSci
Kotlin, Android, Bluetooth, PostgreSQL
Welltok
Android, React Native, React
Experience
Availability
Part-time
Preferred Environment
Android, React Native, React, JavaScript
The most amazing...
...thing I've done is use Bluetooth Low Energy devices for indoor navigation. I worked on the YouVerison Bible Android app with 100+ million downloads.
Work Experience
Android Developer
2021 - 2023
Goldman Sachs - Main
- Became a part of different teams that were maintaining the Marcus Android app. Integrated the app with Plaid services.
- Performed a complete rebrand of the app, changing the colors and fonts and paying special care to accessibility issues.
- Rewrote the app in the new architecture, switching from Conductor and Epoxy to Jetpack Compose.
Technologies: Android, RxJava 2, Model View Intent (MVI)
Senior Android Developer
2019 - 2020
MediSci
- Worked on integrating Bluetooth iHealth devices for measuring blood pressure and glucose in the blood.
- Implemented graphs for displaying blood pressure and glucose results to patients. Users can filter results by day, week, month, or year.
- Worked closely with the designers to make the app intuitive and easy to use, so that users can easily check their next trial visit and their available payments.
- Integrated an AWS Cognito service for user authentication. Integrated continuous integration using CircleCI and Fastlane for easy distribution of test and production releases, and also integrated Sentry service for error tracking.
- Maintained and published the app on Google Play Store.
Technologies: Kotlin, Android, Bluetooth, PostgreSQL
Senior React Native Developer
2018 - 2020
Welltok
- Maintained and implemented new functionalities into the existing CafeWell app.
- Converted the app's code completely to support the newest AndroidX libraries and also converted the remaining parts of code written in Java to Kotlin.
- Helped the team improve and stabilize back-end services written in Java, Ruby, and Node.js.
- Rewrote the old Android and IOS app in React Native.
Technologies: Android, React Native, React
Senior Android Developer
2017 - 2019
Temptime
- Built Temptime's Android app using the new Camera 2 APIs to detect the changes in the color of a temperature sensor that is injected on a QR barcode.
- Took part in a larger project to develop the first miniaturized technology to monitor temperature exposure of vials containing the oral polio vaccine, which satisfies the World Health Organization’s (WHO) PQS VVM performance specification.
- Used the latest technology stack when it comes to the app's deployment.
Technologies: Java, Android, PostgreSQL
Senior Android Developer
2017 - 2018
FlumeTech
- Rewrote the app using MVVM and Android architecture components.
- Integrated QR barcode detection and an intercom.
Technologies: Java, Android
Android Developer
2017 - 2017
YouVersion (via Toptal)
- Wrote tests and made sure that the app's main functions were properly implemented.
Technologies: MVVP, Room, Dagger 2, OkHttp, Gradle, GitLab, Espresso, Android, Kotlin
Android Developer
2017 - 2017
Pangea (via Toptal)
- Created an Android app to communicate with a Bluetooth-connected watch that can measure heart rate and level of oxygen inside a patient's blood.
- Processed byte data received from the device and transformed the data into usable Java classes.
- Made login/register flow, syncing data with the server.
- Enabled the back-end to control the device thorough the Android app.
Technologies: Espresso, Retrofit 2, Gradle, RxJava 2, REST, Android, Bluetooth
Senior Android Developer
2016 - 2017
FuboTV (via Toptal)
- Created a streaming app that can play sports channels on the mobile device, save them for later watching, and list all the sports events two weeks in advance.
- Built the app from the ground up, proposing tools, libraries, and overall solutions to make the app and code base in a clean and testable way.
Technologies: Model View Presenter (MVP), Glide, Retrofit, Dagger 2, Gradle, Java, Android
Senior Android Developer
2016 - 2016
Pulsr (via Toptal)
- Created a reusable, cross-platform social network app that can propose events to go to or guide you to the important places inside the selected city.
- Worked with an existing codebase, refactoring the app to be as testable as possible.
- Introduced the Google Maps API.
Technologies: Clean Architecture, Glide, Realm, Retrofit, Java, Android
Senior Android Developer
2016 - 2016
Bosch
- Worked on a device that connects to the car's onboard computer over Bluetooth using an ODB interface and then extracts, process, and displays all the relevant data like errors on the car, trip logs, last parked position, etc., on the Android device.
Technologies: Bluetooth, Java, Android
Senior Android Developer
2015 - 2016
MERA Software Services
- Worked on an app that streams various TV content to mobile devices using HLS and Media Player frameworks.
- Integrated different type of analytics (Nielsen, Omniture and Comscore) to the existing video player.
Technologies: ExoPlayer, Glide, Dagger, GSON, Retrofit, Android SDK, Java
Android Developer
2014 - 2015
PsTech
- Worked for Sony and contributed to projects for Plantronics.
- Developed features for a smart Bluetooth fitness watch, using Bluetooth Low Energy (BLE) for communication between device and phone.
- Implemented features and maintained the calendar and alarm applications for Sony Mobile.
- Developed a small Android app for indoor navigation using Bluetooth Low Energy (BLE) beacons.
Technologies: Android SDK, Java
Android Developer
2012 - 2014
Mitec, d.o.o
- Developed a chat application with integrated data encryption.
- Developed a SQLite database and complete UI of the application.
Technologies: Android SDK, Java
Web Developer
2009 - 2009
Univerzijada 2009
- Built a dynamic picture gallery and a scoreboard with live results.
- Maintained the Univerzijada website.
Technologies: MySQL, PHP
Experience
Awe Everywhere
AWE is the powerful app platform for branded video delivery and engagement across all major platforms.
Sony Mobile Calendar and Alarm
Custom Sony Mobile Calendar and Alarm app.
Skills
Languages
Kotlin, JavaScript 6, Java, PHP, SQL, Python, C, JavaScript, TypeScript, C++
Frameworks
Dagger 2, Android SDK, React Native, Dagger, Glide, Espresso
Libraries/APIs
Retrofit, Retrofit 2, REST APIs, RxJava 2, SQLBrite, RxJava, React, GSON
Tools
GitLab, GitHub, AutoValue, Eclipse IDE, Android Studio, Gradle, ExoPlayer
Paradigms
Agile Software Development, Model View Presenter (MVP), Model View ViewModel (MVVM), Clean Architecture, Android Material Design, REST, MVVP, Model View Intent (MVI)
Platforms
Android
Storage
MySQL, PostgreSQL, Realm
Other
GitFlow, OkHttp, Video Streaming, Bluetooth, Room, WebSockets
Education
2002 - 2013
Bachelor's (Hons) Degree in Electrical Engineering and Computing (Computer Science and Informatics)
Faculty of Mathematics - Belgrade, Serbia
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