About myself


Since 2012, I have specialised in mobile development for the Android platform. Creating apps for millions of users across the globe is what excites me. Therefore, a clean architecture, maintainable and testable code, and an offline-first approach for spotty cellular networks are must have requirements for modern Android apps. Using Kotlin in product apps, makes development faster while integrating seamlessly with existing Java code.

IoT - Internet of Things

In today's world, everything is becoming connected and the IoT market is rapidly growing. No matter if you want to connect your Android app to hardware via Bluetooth or create connected devices for consumer, retail, or industry applications based on Android Things, I rapidly prototype and develop new services.

Voice Assistant

It's clear that voice assistants are going to have an impact on our lives beyond our imagination: they are extremely easy to use and save us time on a daily basis. They are changing human interaction with devices and the Internet. Successful marketing/branding/sales will adapt and never be the same again. I'm happy to help you enter that rapidly growing market and implement your brand's personal assistant.

Ralf Gehrer

As an experienced Java full-stack developer, I have been working on distributed systems handling big data. In particular, I have been designing, implementing, and optimizing algorithms for large scale data processing and analyses, such as duplicate detection, similarity search, and data mining.

Since 2012, I have specialised in mobile app development for Android. I'm happy to be using Kotlin in production apps and am passionate about IoT solutions - be it the hardware interactions via Bluetooth or creating services and connected sensors via the Android Things platform.

Besides valuing high quality code and software design, I’m a fast learner and enjoy working on challenging tasks either in the corporate world or in an entrepreneurial environment. I have gained substantial experience at medium-sized companies (e.g. smartShift, GoEuro) as well as large enterprises (e.g. SAP AG, Deutsche Bahn AG, Mercedes Benz AG). Further, I co-founded a tech-startup (ecotastic), where I was serving as CTO.

Regarding my education, I graduated in 2012 with honors from the Hasso-Plattner Institute, Potsdam with a Master of Science in Software Engineering. During my studies, I spent a year abroad at the University of California, San Diego on a Fulbright scholarship and completed the basic track in Design Thinking at the HPI School of Design Thinking. Additionally, I participated in the Global Team-based Product Innovation and Engineering course (ME310) at the Stanford University.
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What Clients Say About Me

Viraj Tank

Mobile Team Lead at MBition Mercedes-Benz Innovation Lab

Ralf joined our development team at MBition as a Freelance developer between Oct-2018 and Dec-2018. Right from the beginning of this short but time critical and crucial project Ralf, not only took end to end responsibility for his user stories, but he also helped other developers where help was needed. Ralf is dedicated, flexible and full of getting it done attitude. One of the best developer I have worked with. Thank you, Ralf, for all the hard work, your contribution and commitment made the project a big success, looking forward to working with you in the future.

Valeria Carretto

IoT Project Manager at Nestlé

Ralf worked on several IoT projects in Nespresso as Android developer and he is one of the best developers I worked with. Not only technically strong and independent, Ralf is a trustworthy, proactive and serious professional. Good team player, committed to the success of the project, able to lead a team of developers and coordinate with different stakeholder. I hope I will have the chance to work again with him in the future.

Florian Winkler

Development Architect, SAP

We had hired Ralf as an Android specialist to help us develop an SDK for mobile applications in the Healthcare industry and for building a reference application that would show how to use it. Ralf’s contribution to that was outstanding and highly professional. Not only is he an expert of the Android platform who could provide valuable tips and best practices, but also his mindset and can-do attitude made him an excellent extension to our team from day one. Ralf worked independently on tasks and made sure to pro-actively align with the other team members so that things would fit and could be improved if necessary. His results for both the SDK and application were exceeding our expectations. Furthermore, Ralf is a kind person and a team player making it a real pleasure to work with him. We wish him all the best for his future career and would be happy to work with him again!

Patrick Schweizer

Tech Lead, GoEuro

We had an excellent experience working with Ralf on two projects. We hired him to develop the first version of our custom SEO system as well as our Android App in order to meet important deadlines. Ralf proved to be extremely professional and effective. From conceptual design through deployment of the SEO system or launch of the mobile app respectively our experience was fantastic and I highly recommend Ralf.

Sebastian Stricker

Head of ShareTheMeal.org

It was a pleasure to work with Ralf. He is extremely professional and with his drive was a great addition to our Android development team. Despite our aggressive timeline and requirements, Ralf delivered beyond expectations. The project he worked on increased the donated amount of our users significantly and enabled us to launch our Android App in new markets. We thank Ralf very much for his support and wish him all the best for his further projects.

Latest Posts

Android Camera Util Project

It seems to be the simplest thing in the world: taking a picture within your Android app using the default camera activity. However, there are many…

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Get In Touch

Contact Details

If you are seeking freelance software engineers for your project or company, please don't hesitate to contact me. I'm looking forward to hearing from you. (By submitting the contact form you consent to us storing the transferred information in order to respond to your inquiry.)

+49 162 54 88 671
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