Konstantin S.

iOS developer

Konstantin is a senior iOS developer with over 15 years of experience, specializing in mobile architecture, security, and performance. He has extensive expertise in Swift, Objective-C, UIKit, and SwiftUI, delivering secure, high-performance applications across fintech, communications, and event technology domains.

At Mode Software, Konstantin led the development of a post-quantum-secure encrypted messaging application, integrating WebRTC, Rust libraries, and local data storage with Realm. Earlier in his career, he built and launched the Appy Couple platform from the ground up, scaling it to over 500,000 downloads and achieving a 4.8 rating on the App Store.

Konstantin brings a strong focus on clean, user-centric development combined with mentoring and technical leadership. He works effectively in remote, cross-functional teams and excels in security-driven product environments.

Main expertise

  • Mobile 12 years
  • iOS
    iOS 12 years
  • Swift
    Swift 10 years

Other skills

  • Google Maps
    Google Maps 3 years
  • CSS
    CSS 2 years
  • Apple Maps
    Apple Maps 2 years
Konstantin

Konstantin S.

Germany

Get started

Selected experience

Employment

  • Senior iOS Developer

    Mode Software Inc. - 6 years 2 months

    Mode Software Inc. is a Canadian software company that specializes in privacy-focused communications, developing secure messaging and collaboration tools with advanced cryptographic systems.

    • Created and maintained a secure messaging app that used post-quantum encryption, providing top-tier data protection for users.
    • Implemented WebRTC-based voice and video calls, designing custom call interfaces and enhancing call stability and media quality.
    • Integrated a shared Rust library used across mobile and desktop clients, ensuring strong encryption, serialization, and consistent storage.
    • Collaborated with Android and backend teams to improve decentralized data storage and double encryption performance.
    • Wrote detailed technical documentation, led release planning, and coordinated with QA to improve testing and deployment.

    Technologies:

    • Technologies:
    • iOS iOS
    • Swift Swift
    • UIKit UIKit
    • CoreData CoreData
    • Rust Rust
    • Realm Realm
    • Objective-C Objective-C
    • WebRTC WebRTC
    • Fastlane Fastlane

  • iOS Developer

    Appy Couple - 2 years 10 months

    Appy Couple is a U.S.-based technology company providing a customizable wedding and event management platform via web and mobile apps.

    • Led the development of the Appy Couple and Appy Life iOS apps from concept through release, achieving over 500K downloads and a 4.8/5.0 rating on the App Store.
    • Created complex UI components with an in-app content editor and more than 1,000 customizable templates for event pages.
    • Built robust offline data storage systems, reducing server load and enhancing user experience.
    • Improved app performance and memory management, significantly increasing responsiveness and stability across multiple iOS versions.

    Technologies:

    • Technologies:
    • Swift Swift
    • UIKit UIKit
    • CoreData CoreData
    • Git Git
    • Objective-C Objective-C
    • REST API REST API

  • iOS Developer (Freelance)

    Toptal - 5 years 2 months

    Toptal is a global network connecting top freelance developers, designers, and engineers with clients worldwide.

    • Delivered over 10 iOS applications from scratch for U.S. startups and mid-sized companies, covering design, implementation, and deployment.
    • Created a dating app platform and multiple white-label apps based on it, enabling faster client rollouts and modular customization.
    • Worked as part of a six-developer team to maintain and improve a medical diary app, enhancing data synchronization and reliability.
    • Supported existing apps with updates, new features, and App Store maintenance.
    • Guided clients on App Store compliance and CI/CD pipeline setup.

    Technologies:

    • Technologies:
    • Swift Swift
    • UIKit UIKit
    • CoreData CoreData
    • Unit Testing
    • Git Git
    • Objective-C Objective-C
    • REST API REST API
    • Fastlane Fastlane

Education

  • Standalone courseInformation Technologies and Computer-Aided Systems

    Perm National Research Polytechnic University · 2012 - 2013

  • BSc.Software Development

    Perm College of Technology and Chemistry · 2005 - 2009

Portfolio

  • Speak Pro: Shadowing Lessons - 1
  • Mode - Secure Communication Platform - 1

Find your next developer within days, not months

In a short 25-minute call, we would like to:

  • Understand your development needs
  • Explain our process to match you with qualified, vetted developers from our network
  • You are presented the right candidates 2 days in average after we talk

Not sure where to start? Let’s have a chat

First developer starts within days. No aggressive sales pitch.