Jaanus Siim, Software Developer in Tartu, Estonia
Jaanus Siim

Software Developer in Tartu, Estonia

Member since April 18, 2015
Jaanus is a highly skilled software developer with a passion for mobile development. In recent years he has focused on iOS development but also has extensive experience with Android and J2ME platforms. Jaanus is a great communicator and enjoys working in diverse environments.
Jaanus is now available for hire



  • Object-oriented Programming (OOP) 9 years
  • Objective-C 7 years
  • Xcode 7 years
  • iOS 6 years
  • AppCode 5 years
  • Swift 2 years
  • SpriteKit 2 years


Tartu, Estonia



Preferred Environment

Swift, Objective-C, iOS

The most amazing...

...things I've coded are J2ME games on feature phones. Squeezing every part of code and resources to fit the application into 64kB jars was special.


  • Freelance iOS Developer

    2012 - PRESENT
    Coodly OÜ
    • Led the development of taxi ordering app Taxify, currently taking off in Europe.
    • Led the development of Taxify companion app Taxify Driver.
    • Led the development of the WeAreColony iPad app to watch indie movies.
    • Created multiple iPad quiz apps used in local bars and shopping centers.
    • Led the development of Speed Camera Tracker showing useful info for drivers in Australia.
    • Built multiple in-house apps to play around with new technologies like Swift and SpriteKit.
    Technologies: iOS
  • Senior iOS Developer

    2013 - 2014
    Mooncascade OÜ
    • Led the development of TrasnferWise iOS client. Defined app architecture and network communication with caching.
    • Extended functionality of Parku (v2) iOS app.
    • Rewrote the parku app (v3) targeting iOS 7 and up.
    • Led the development of KFC Heartbeat, a social app based on Glassboard and used internally by KFC.
    • Fixed bugs and improved functionality for CarDelMar car rental app.
    • Developed a simple utility calculator for the golden ratio.
    • Maintained various existing iOS projects.
    Technologies: iOS
  • Senior J2ME and iOS Developer

    2009 - 2012
    MobiSolutions AS
    • Led the UI rewrite of Skype J2ME.
    • Helped intermittently on Skype's Android version.
    • Led the development of a marine navigation iOS app built on top of a C++ library provided by the client.
    • Led the developmet to extend Touchnote iOS app's functionality. First extended image editing capabilities and later did partial UI rewrite for universal app.
    • Led the development of Lifecake iOS app. Scrapbook for memories of kids growing up. Notes, photos an videos that can be shared with family.
    • Led the development of a local parking iOS app.
    Technologies: Android, iOS, J2ME
  • Senior Java Developer

    2008 - 2009
    Nutiteq OÜ
    • Led the development of a mapping SDK that could be used on any platform supporting Java (J2ME, Android, BlackBerry).
    • Extended the functionality of the mapping application written in J2ME.
    Technologies: Java, Mobile App Development
  • Test Engineer: J2ME Games, Java Server Development

    2004 - 2008
    Aqris Software AS
    • Developed custom testing framework on top of IBM STAF framework.
    • Wrote J2ME games for Sulake.
    • Wrote banking loan solutions on top of Spring framework.
    • Wrote PAF casino games using a custom in-house framework.
    Technologies: Spring, J2ME


  • Loquiz

    A platform for real-world location-based games with support for different game types. It is used by event companies, outdoor companies, schools, and others who need to create cool location-based games fast.

    Coming in, I originally moved Objective-C based code gradually to Swift and envisioned a rules-based system where you would encapsulate game type-specific logic in discrete units that can be swapped out at runtime. It has worked out beautifully.

    Now we're moving to real-time interactive multi-player games using Firestore live updates. This has also meant moving the app from a custom back-end API to using Firestore and Firebase storage.

    The good:
    * Unit tests for rules system allowed moving forward faster without the fear of breaking things. Of course, there could always be more unit tests.
    * Feature flags in the main branch enable experimenting while delivering public releases.
    * Abstracting back-end communication from core game logic allowed for an easier transition from the own API to Firestore saving.

  • Your Daily Calories

    This is a personal project for calorie tracking.

    Based on your fitness goals, you may want to target consumed calorie deficit or surplus. Using Apple Watch, you will be given your basal and active calories burned.
    Your daily calories' information will combine calories burned and consumed and project your deficit or surplus target in a 24-hour window. This will allow you to make educated decisions on how to adjust your activity or eating.

    The food database will be built by yourself, considering a very tailored list of products specific to your region and preferences: over the last two years, I built a list of 350 foods and products.

    Everything is backed up to iCloud and there are no third-party services involved.

    HealthKit, SwiftUI, UIKit, CoreData, CloudKit, WidgetKit, IAP

  • Find Movies to Watch

    Using The Movie Database (TMDb), discover what is available in your region to rent or purchase on iTunes or streamable on Netflix. Browse movies by rating, popularity, and genres. Put movies into the watchlist to check out later.

    Technical stack: The Movie Database API, iTunes Search API, CloudKit, CloudKit JS, CoreData, UIKit, Google Ads, IAP

  • Taxify iOS

    Taxify gets you a taxi at the push of a button. The company is taking off at the moment in Europe. I led development for the native rewrite for version 2.0.

    Technical notes: Core Location, Core Data, Google Maps SDK, AFNetworking

  • TenPair

    A simple ten-pair puzzle game. Personal project to get familiar with SpriteKit on iOS. For version 1.2, the whole project was rewritten in Swift.

    Technical notes: Swift, SpriteKit, iAd

  • Gambrinus

    Estonia's biggest beer blog on iOS devices. It pulls posts from tartugambrinus.blogspot.com using Blogspot API. Done in cooperation with owner of the blog. The iPad version runs in kiosk mode also browsable in the beer shop owned by the blog writer.

    Technical notes: Core Data, AFNetworking Blogspot API, Guided Access, Images Caching, UIKit


  • Languages

    Swift, Objective-C, Java
  • Frameworks

    iPhone SDK, Core Data, AFNetworking, StoreKit, Core Location, Spring, MapKit, CloudKit, UIKit
  • Tools

    Interface Builder, Xcode, AppCode, Git, GitHub
  • Platforms

    iOS, iAd, J2ME, Android, Mapbox
  • Other

    iPad, Mobile App Development, iBeacon, Widgets, Mobile Ads
  • Libraries/APIs

    SpriteKit, Braintree API, PayPal API, Google Maps, HealthKit
  • Paradigms

    REST, Object-oriented Programming (OOP), Agile Software Development
  • Storage

    Cloud Firestore, SQLite, PostgreSQL


  • Bachelor's Degree in IT
    2001 - 2003
    Tallinn Technical University - Tallinn

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