Iliyan is available for hire

Iliyan Germanov

Verified Expert in Engineering

Android Developer

Location

Sofia, Bulgaria

Toptal Member Since

March 30, 2022

Iliyan co-founded Ivy Apps and built Ivy Wallet: an open-source money manager with 80,000+ installs, a 4.8/5 rating, and 2,797 reviews on the Google PlayStore. The YouTube tech community recognized Ivy Wallet as the best Android UI/UX in 2021. Iliyan is also a functional programming and Kotlin expert. He built from scratch the institutional-grade security Qredo Signing App and developed the fintech mobile wallet: phyre—including its white-label products—which combined have 300,000+ customers.

User Interface (UI)UX Architecture Android Design Guidelines User Experience (UX)Google Play Store Android Testing Mobile Security Cryptography Android Performance Optimization Push Notifications Back-end Open Source Jetpack Compose Object-oriented Programming (OOP)Mobile Push Notification Room Database Haskell Reactive Programming

Portfolio

Ivy Apps

Jetpack Compose, User Interface (UI), User Experience (UX), Kotlin...

Reddit, Inc.

Android, Kotlin, Java, Android Studio, REST APIs, Android SDK, Android Jetpack

Qredo

Kotlin, Android SDK, Mobile, Android Studio, Ubuntu Linux...

Experience

Android - 10 years Mobile UX - 8 years Android SDK - 8 years Mobile Architecture - 7 years Mobile Security - 6 years Kotlin - 5 years Functional Programming - 5 years Jetpack Compose - 2 years

Availability

Part-time

Preferred Environment

Ubuntu Linux, Android Studio, GitHub, Jira, Android, Agile

The most amazing...

...app I've built is Ivy Wallet, an open-source money manager app with 80,000+ installs and a 4.8/5 rating, recognized for its UI/UX by the YouTube tech community.

Work Experience

Chief Technical Officer | Co-founder

2019 - PRESENT

Ivy Apps

Developed Ivy Wallet as a solo developer and received ten awards for the best Android UI/UX in 2021 from the YouTube tech community without having a marketing budget.
Completed the "7-day product challenge" that we created, which involved developing an Ivy Wallet MVP in 7 days or less. It now has 80,000+ installs and a rating of 4.8 out of 5, with 2,797 reviews and 24,000+ active users.
Created and led the Ivy Wallet open-source project, which now has more than 850 stars, over 151 forks, and 35 contributors on GitHub.
Built an app called Ivy Task from scratch. It is a simple yet powerful task management app for Android devices with a slick UI/UX.
Designed, developed, and launched four startups with my co-founder, which we launched into production without external financing.

Technologies: Jetpack Compose, User Interface (UI), User Experience (UX), Kotlin, Android Studio, Ubuntu Linux, Object-oriented Programming (OOP), OOP Designs, SQL, Android SDK, Mobile, Android, Haskell, Functional Programming, REST, Mobile Security, Android Jetpack, Firebase, Architecture, UX Architecture, Git, Scrum, App UX, APIs, Back-end, Spring Boot, Material Design, Machine Learning, HTML5, Figma, Adobe Experience Design (XD), Python, Elm, Elm Architecture, Jira, Open Source, GitHub, CI/CD Pipelines, Unit Testing, Automated UI Testing, QA Testing, GitLab, Mobile UX, Agile Software Development, Startups, PostgreSQL, Google Play Console, Google Play Store, Mobile Apps, Mobile UI, App Store Optimization (ASO), Software Design, Mobile Architecture, Mobile APIs, Microsoft Teams, Android Performance Optimization, Gradle, Proguard, Android Design Library, Retrofit 2, RoomDB, Dagger 2, OkHttp, Arrow, Android Design Guidelines, Push Notifications, Coroutines, Android Testing, Model View ViewModel (MVVM), Dependency Injection, Android Material Design, Test-driven Development (TDD), Firebase Cloud Messaging (FCM), Android Debug Bridge, SQLite, Functional Reactive Programming, REST APIs, Reactive Programming, Google In-app Billing, Google Mobile Services (GMS), Firebase Analytics, Firebase Android SDK, CTO

Android Engineer

2022 - 2022

Reddit, Inc.

Worked in Reddit's i18n discovery team to improve the discovery of high-quality local content on Reddit.
Introduced new features as experiments while having full ownership of the engineering quality and execution of the given project (NDA).
Developed high-quality code using engineering best practices like modularized architecture, unit testing, and methods to reduce software complexity and increase maintainability.

Technologies: Android, Kotlin, Java, Android Studio, REST APIs, Android SDK, Android Jetpack

Lead Mobile Developer

2021 - 2022

Qredo

Led the development of Qredo mobile, launched a secure product with an exceptional UI/UX on time, and closed an $80 million series A round.
Developed the Qredo Signing app for Android from scratch that safeguards more than $3 billion worth of crypto by providing a secure and robust way to approve or reject requests on the Qredo Network.
Got assigned to lead the Qredo iOS app development, which had a lot of technical debt at the time. Fixed the team in less than three months by guiding them to implement the clean and scalable architecture.

Technologies: Kotlin, Android SDK, Mobile, Android Studio, Ubuntu Linux, Object-oriented Programming (OOP), OOP Designs, SQL, C, Android, Jetpack Compose, User Interface (UI), User Experience (UX), Haskell, Blockchain, Functional Programming, Cardano Blockchain, REST, Mobile Security, Cryptography, Android NDK, Android Jetpack, Architecture, UX Architecture, Git, Scrum, App UX, APIs, Material Design, Figma, Elm Architecture, Jira, Open Source, GitHub, CI/CD Pipelines, Unit Testing, Automated UI Testing, QA Testing, GitLab, Mobile UX, Agile Software Development, Startups, PostgreSQL, Google Play Console, Google Play Store, Mobile Apps, Mobile UI, App Store Optimization (ASO), Software Design, Mobile Architecture, Mobile APIs, Microsoft Teams, Android Performance Optimization, Gradle, Proguard, Android Design Library, Retrofit 2, RoomDB, Dagger 2, OkHttp, Arrow, Android Design Guidelines, Push Notifications, Coroutines, Android Testing, Model View ViewModel (MVVM), Dependency Injection, Android Material Design, Test-driven Development (TDD), Firebase Cloud Messaging (FCM), Android Debug Bridge, SQLite, Functional Reactive Programming, REST APIs, Reactive Programming, GraphQL, Google Mobile Services (GMS), Firebase Analytics, Firebase Android SDK

Senior Android Developer

2020 - 2021

Qredo

Developed the Qredo Signing Android App from scratch as a solo developer and launched it to production in less than a month and a half.
Designed the clean, secure, and scalable architecture for the Qredo Android app to pass all certifications required and be the UI for trading billions of dollars worth of crypto used by institutional investors.
Improved the Android app proactively in terms of UI and UX by suggesting ideas and best practices to the design team while maintaining a flawless code-base. Got promoted to take charge of the iOS team.

Technologies: Kotlin, Android, Android Studio, Ubuntu Linux, Object-oriented Programming (OOP), OOP Designs, SQL, C, Android SDK, Mobile, Jetpack Compose, User Interface (UI), User Experience (UX), Blockchain, Functional Programming, Cardano Blockchain, REST, Mobile Security, Cryptography, Android NDK, Android Jetpack, Architecture, UX Architecture, Git, Scrum, App UX, APIs, Material Design, Figma, Elm Architecture, Jira, Open Source, GitHub, CI/CD Pipelines, Unit Testing, Automated UI Testing, QA Testing, GitLab, Mobile UX, Agile Software Development, Startups, PostgreSQL, Google Play Console, Google Play Store, Mobile Apps, Mobile UI, App Store Optimization (ASO), Software Design, Mobile Architecture, Mobile APIs, Microsoft Teams, Android Performance Optimization, Gradle, Proguard, Android Design Library, Retrofit 2, RoomDB, Dagger 2, OkHttp, Android Design Guidelines, Push Notifications, Coroutines, Android Testing, Model View ViewModel (MVVM), Dependency Injection, Android Material Design, Test-driven Development (TDD), Firebase Cloud Messaging (FCM), Android Debug Bridge, SQLite, Functional Reactive Programming, REST APIs, Reactive Programming, GraphQL, Google Mobile Services (GMS), Firebase Analytics, Firebase Android SDK

Android Lead

2016 - 2019

Phyre

Leveraged the Phyre mobile payment software development kit (SDK) that we created to develop the A1 Wallet, VivaPay, and BACB Pay white-label mobile wallets.
Hired two senior Android engineers to scale the Android team and deliver all the required features and improvements on time.
Maintained and developed mobile payment apps similar to Revolut used for millions of transactions and transfers daily.

Technologies: Kotlin, Android, Android Studio, Ubuntu Linux, Object-oriented Programming (OOP), OOP Designs, SQL, Java, C, Android SDK, Mobile, User Interface (UI), User Experience (UX), Mobile POS, Functional Programming, REST, Mobile Security, Cryptography, Android NDK, Android Jetpack, Digital Payments, Android POS, Firebase, Architecture, UX Architecture, Git, Scrum, App UX, APIs, HTML, Back-end, JavaScript, Spring Boot, Material Design, Machine Learning, TensorFlow, HTML5, Figma, Adobe Experience Design (XD), Python, Jira, Open Source, GitHub, CI/CD Pipelines, Unit Testing, Automated UI Testing, QA Testing, GitLab, Mobile UX, Agile Software Development, Startups, PostgreSQL, Google Play Console, Google Play Store, Mobile Apps, Mobile UI, Software Design, Mobile Architecture, Mobile APIs, CSS, Android Performance Optimization, Gradle, Proguard, Android Design Library, Retrofit 2, RoomDB, Dagger 2, OkHttp, Slack, Android Design Guidelines, Push Notifications, Coroutines, Android Testing, Model View ViewModel (MVVM), Dependency Injection, Android Material Design, Test-driven Development (TDD), Firebase Cloud Messaging (FCM), Android Debug Bridge, SQLite, Functional Reactive Programming, REST APIs, Reactive Programming, GraphQL, Google In-app Billing, Google Mobile Services (GMS), Mixpanel Android API, Firebase Analytics, Firebase Android SDK

Android Developer

2016 - 2016

Phyre

Received an award for the fastest MasterCard mobile payment project for Eastern Europe by implementing mobile payments and getting certified by MasterCard in a record time. I was the only Android developer at the time, and I worked part-time.
Scaled the Phyre mobile apps to more than 100,000 active users by creating one of the first mobile wallets in Bulgaria and introducing tons of valuable features to everyday consumers.
Cleaned the technical debt I created during the rush for financing, implemented clean architecture, and started scaling the team while already maintaining a large active user base.

Technologies: Java, Android, Mobile POS, Android Studio, Object-oriented Programming (OOP), OOP Designs, SQL, C, Kotlin, Android SDK, Mobile, User Interface (UI), User Experience (UX), REST, Mobile Security, Cryptography, Android NDK, Android Jetpack, Digital Payments, Android POS, Firebase, Architecture, UX Architecture, Git, Scrum, App UX, APIs, HTML, Back-end, JavaScript, Spring Boot, Material Design, Machine Learning, TensorFlow, HTML5, Figma, Adobe Experience Design (XD), Python, Jira, Open Source, GitHub, Unit Testing, Automated UI Testing, QA Testing, GitLab, Mobile UX, Agile Software Development, Startups, PostgreSQL, Google Play Console, Google Play Store, Mobile Apps, Mobile UI, Software Design, Mobile Architecture, Mobile APIs, CSS, Android Performance Optimization, Gradle, Proguard, Android Design Library, Retrofit 2, OkHttp, Slack, Android Design Guidelines, Push Notifications, Coroutines, Android Testing, Model View Presenter (MVP), Model View ViewModel (MVVM), Dependency Injection, Android Material Design, Test-driven Development (TDD), Firebase Cloud Messaging (FCM), Android Debug Bridge, SQLite, REST APIs, Reactive Programming, Google In-app Billing, Google Mobile Services (GMS), Mixpanel Android API, Firebase Analytics, Firebase Android SDK

Android Developer

2014 - 2016

Freelance

Implemented private encrypted chat communication in CSipSimple which is an open source project; the URL is Openhub.net/p/CSipSimple. Every user has their own private password arranged in the back end which was client provided.
Built an app that allows a user to remotely wipe a device’s data through a specific push notification or call from a target number. Once the app is installed, it becomes hidden so thieves don't remove it.
Designed and built advanced native applications for the Android platform.
Worked with outside data sources and APIs, managed data with SQLite, and ensured the best possible performance, quality, and responsiveness of the application.
Encrypted data with algorithms from AES (Advanced Encryption Standard).
Implemented push notifications with GCM (Google Cloud Messaging).
Managed Android device policies and refactored and optimized outdated code.

Technologies: Android, Android SDK, Android Studio, Java, User Interface (UI), User Experience (UX), Operating Systems, Object-oriented Programming (OOP), OOP Designs, Mobile, REST, Firebase, Architecture, UX Architecture, Git, App UX, APIs, HTML, Back-end, JavaScript, Spring Boot, Material Design, Machine Learning, Scrum, TensorFlow, HTML5, Figma, Adobe Experience Design (XD), Python, Jira, Open Source, GitHub, Unit Testing, QA Testing, C++, Mobile UX, Agile Software Development, Startups, Google Play Console, Google Play Store, Mobile Apps, Mobile UI, App Store Optimization (ASO), Software Design, Mobile Architecture, Mobile APIs, CSS, Gradle, Proguard, Android Design Library, Retrofit 2, OkHttp, Slack, Android Design Guidelines, Push Notifications, Android Testing, Model View Presenter (MVP), Model View ViewModel (MVVM), Dependency Injection, Android Material Design, Test-driven Development (TDD), Firebase Cloud Messaging (FCM), Android Debug Bridge, SQLite, REST APIs, TCP/IP, Bluetooth, Google In-app Billing, Google Mobile Services (GMS)

Android Developer Intern

2015 - 2015

Luxoft

Developed a mobile application that allows you to control the media in your automobile.
Established and handled the connection with the car's infotainment system. through SDLP (Smart Device Link Protocol).
Created a responsive and interactive user interface (UI).
Improved and optimized the performance of existing applications.

Technologies: Android, Android SDK, Android NDK, Java, Android Studio, App UX, Operating Systems, Object-oriented Programming (OOP), OOP Designs, Mobile, User Interface (UI), User Experience (UX), REST, UX Architecture, Git, APIs, Material Design, Scrum, GitHub, QA Testing, C++, Mobile UX, Agile Software Development, Mobile Apps, Mobile UI, Software Design, Mobile Architecture, Mobile APIs, Gradle, Proguard, Android Design Library, Retrofit 2, OkHttp, Slack, Android Design Guidelines, Push Notifications, Android Testing, Model View Presenter (MVP), Dependency Injection, Android Material Design, Test-driven Development (TDD), Firebase Cloud Messaging (FCM), Android Debug Bridge, SQLite, REST APIs, TCP/IP, Bluetooth, Google Mobile Services (GMS)

Experience

Ivy Wallet | Money Manager

https://github.com/Ivy-Apps/ivy-wallet

Ivy Wallet is an open-source money manager app for Android. It is a free budget manager and spending tracker app that helps users manage their finances. I wrote it using Kotlin, Jetpack Compose, and the latest Android tech stack. The YouTube tech community awarded it ten awards for the best Android UI/UX in 2021.

Reddit Android App

https://play.google.com/store/apps/details?id=com.reddit.frontpage&hl=en&gl=US

Worked in Reddit's i18n discovery team to improve the discovery of high-quality local content on Reddit. I introduced new features as experiments while fully owning the project's engineering quality and execution.

Qredo: Signing App

https://play.google.com/store/apps/details?id=com.qredoapp

The Qredo Signing App enables the secure authorization and approval of transactions on the Qredo Network.

The Qredo Network is the world’s first decentralized multi-party computation solution for digital assets.

It provides a secure layer two peer-to-peer trading network that:
• Facilitates instant cross-chain atomic swaps.
• Provides institutional-grade security and decentralized custody.

Benefits of the Qredo Signing App
• Secure multi-factor authentication using biometrics, a 6-digit pin, and a master seed.
• Instant notifications when a trade has been initiated.

Key Functions
• Enables logging in to the Qredo Network.
• Approval of requests from other users to join the Qredo Network.
• Authorization and approval of addresses.
• Authorized custodians can approve transactions to be secured on the Qredo blockchain.

Get Started
Visit the Qredo website (Qredo.com/join) to create your account and pair your Signing App with the Qredo Network.

Learn more about Qredo (Qredo.com)

Visit our help center: Support.qredo.com.

Phyre: Digital Wallet for Mobile Payments

https://play.google.com/store/apps/details?id=com.phyreapp

With Phyre you can:

• Pay contactless with your phone, instead of a bank card.
• Send money instantly and with no fees within the Phyre network.
• Open a free BGN or EUR current account in minutes using just your mobile device.
• Easily send bank transfers worldwide just with your phone.
• Use all of your loyalty cards from your phone.
• pay securely online with a free virtual Mastercard
• track your expenses in an easy and intuitive way

Save time and bank fees with Phyre.

📲 Pay at any contactless POS terminal just with your phone.
Get rid of your wallet and feel the freedom to pay just with your phone from any part of the world instantly.

💸 Send and receive instant money transfers within the Phyre network.

🛍️ Get the free virtual Phyre Mastercard and shop online with no risk.

🕵️ Stay in control of your spending.
Track your expenses in real time and get free instant notifications for your payments.

🛡 Pay with bank-grade security.
We take security seriously! Payments in phyre 🔥are processed by Paynetics, an EU licensed e-money institution that is a principal member of VISA and Mastercard. We have a bank-grade security system and our application has been certificated by Mastercard.

A1 Wallet

https://play.google.com/store/apps/details?id=bg.a1.wallet

A1 Wallet allows users to pay with their phones everywhere in the world, send and receive money for free in seconds, make secured online payments with the virtual MasterCard card, use loyalty cards directly from their phones, follow all transactions and get instant notifications, and make contactless payments with their phones.

The app allows users to top up their profiles with their debit or credit card, no matter the issuing bank, or with a bank transfer to the individual A1 Wallet IBAN and then start using their phones for payments at any shop with a contactless PoS terminal.

It also allows users to have all loyalty cards in one place, linking them to the A1 Wallet. There are many available loyalty card templates from international and local brands. Still, users can also add a photo of a non-available loyalty card and have it in the app.

Users can follow all transactions and get instant notifications on every payment made or transaction made for free. A1 Wallet gives them an analysis of their weekly or monthly spending. Phyre is a provider of technical services for A1 BULGARIA.

Ivy | Tasks and To-do List

The only task app worth staying on the first page of users' phones.

Here's what they'll get?
• An intuitive brain extension
• More operational memory
• Less stress and worries
• An easy way to organize life

The app comprises:
• Task widget: manage tasks directly from the smartphone home screen.
• To-do and checklists: create, see, and complete shopping lists, to-dos, and tasks without opening an app, as they'll appear on the home screen just below the clock.
• Personalized experience: from a user's name to their favorite widget color, experience a new way of managing
tasks and life.
• Task prioritization: categorize tasks as high, medium, and low-priority and order them to the user's preference.
• Task categories (premium): organize tasks in categories, such as home, work, and personal, and see them both in the app and the widget.

AutoMedia — Native Android Application for Controlling Car's Infotainment System

An advanced Android application that allows users to control media in their cars through their mobile devices. Different options are available, such as playing different tracks, playing or pausing music, controlling volume, muting or unmuting, choosing bass, middle, or treble, setting balance, and fading graphically by clicking on the place to listen the sound from in the automobile. Connection happens over WiFi by custom SmartDeviceLink (SDL2, github.com/Luxoft/SDLP2) protocol.

Alfred Restaurants

Alfred is an additional restaurant system that allows clients to browse the menu, call the waiter, and order directly from their smartphones. Alfred is an intuitive, fast, instant app delivering a seamless experience in the restaurant.

Slav Squad — The Slav Social Network

A fully functional social media platform similar to Instagram built with Firebase.

Key features:
• Sign up and sign in with Google, Facebook, and email
• Create a highly customizable profile
• Post images
• Like, comment, and share

Publication

The Foundations of Functional Reactive Programming in Android

https://www.toptal.com/android/functional-reactive-programming-part-1

Publication

Future-proof Your Android Code, Part 2: Functional Reactive Programming in Action

https://www.toptal.com/android/functional-reactive-programming-part-2

Skills

Languages

SQL, Java, Kotlin, HTML, JavaScript, HTML5, CSS, GraphQL, C, Haskell, Python, Elm, C++

Frameworks

Android SDK, Spring Boot, Dagger 2

Libraries/APIs

Proguard, Android Design Library, Retrofit 2, REST APIs, Mixpanel Android API, Firebase Android SDK, TensorFlow

Tools

Android Studio, Android NDK, Android Jetpack, Git, Figma, Adobe Experience Design (XD), Jira, GitHub, GitLab, Gradle, Slack, Firebase Cloud Messaging (FCM), Android Debug Bridge, Google Mobile Services (GMS), Firebase Analytics, Microsoft Teams

Paradigms

Object-oriented Programming (OOP), Functional Programming, REST, Scrum, Unit Testing, Agile Software Development, App Store Optimization (ASO), Model View Presenter (MVP), Model View ViewModel (MVVM), Dependency Injection, Android Material Design, Test-driven Development (TDD), Functional Reactive Programming, Reactive Programming, Agile

Platforms

Ubuntu Linux, Mobile, Android, Blockchain, Firebase

Storage

PostgreSQL, RoomDB, SQLite

Other

OOP Designs, Jetpack Compose, User Interface (UI), User Experience (UX), Mobile Security, Cryptography, Digital Payments, Android POS, Architecture, UX Architecture, App UX, APIs, Material Design, Back-end, Elm Architecture, Open Source, CI/CD Pipelines, Automated UI Testing, QA Testing, Startups, Google Play Console, Google Play Store, Mobile UX, Mobile Apps, Mobile UI, Software Design, Mobile Architecture, Mobile APIs, Android Performance Optimization, OkHttp, Arrow, Android Design Guidelines, Push Notifications, Coroutines, Android Testing, Google In-app Billing, Operating Systems, Mobile POS, Cardano Blockchain, Machine Learning, TCP/IP, Bluetooth, CTO

Education

2011 - 2016

Professional Degree in Software Engineering

Technology School Electronic Systems - Sofia, Bulgaria

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.

Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring