Android App Agency from Cologne

Android app development for smartphones & tablets

From the first idea through UI/UX and development to the Play Store release, we support your Android app end-to-end.

Native with Kotlin and Jetpack Compose or cross-platform with Flutter: we build Android apps that run reliably across the entire device landscape – from entry-level smartphones to foldables.

Android app developmentAndroid smartphone app development
The world's largest mobile platform

Why Android development?

Around 70% of all smartphones worldwide run Android – if you want to reach mobile users, there is no way around the platform. We make sure your app makes an excellent impression there.

Maximum reach: from entry-level devices to flagships – an Android app reaches the largest mobile audience, B2C and B2B alike.

Device diversity under control: thousands of device models, screen sizes and Android versions – we test on real devices and ensure quality across the board.

Modern UI with Material Design: with Jetpack Compose and Material 3 we build interfaces that feel at home on every Android device.

Proven in production: from PAGOPACE to the e-prescription integration to Piening Connect – our apps are used by tens of thousands of Android users every day.

Your Android agency for the entire product lifecycle

Our Android services

From concept to operation: we cover the complete lifecycle of your Android app – or strengthen your existing team with our expertise.

Android app development

Building your Android app with Kotlin & Jetpack Compose or Flutter – from MVP to a scalable enterprise solution.

API & backend integration

Connecting REST and GraphQL APIs, push via Firebase Cloud Messaging, in-app billing and Google services such as Maps or ML Kit.

UI/UX with Material Design

Interfaces built to Material 3: Dynamic Color, dark mode and accessibility included – consistent across the entire device landscape.

Tablets, Wear OS & widgets

More than smartphones: we optimise your app for tablets and foldables, bring it to Wear OS and to the home screen as a widget.

Testing & Play Store release

Automated tests on real devices, beta tracks and staged rollouts – for stable releases in the Google Play Store.

Android consulting & team extension

Architecture consulting, code reviews or experienced Android developers for your team – flexible, as needed.
At a glance

The advantages of Android apps

Android combines enormous reach with technical flexibility. These four advantages make the case for the platform:

01

Maximum reach

Around 70% market share worldwide: an Android app reaches the largest mobile audience – in the consumer market and in the enterprise.

02

Flexibility & openness

Background services, deep system customisation and alternative distribution channels: Android gives your product more freedom than any other platform.

03

Fast releases

Short review times and staged rollouts in the Play Store: new features and fixes reach your users without long waits.

04

Deep system integration

NFC, Bluetooth, USB or custom hardware: Android is ideal for companion apps and IoT connections – as our NFC payment ring project shows.

Native with Kotlin or cross-platform with Flutter?

In a free initial consultation we will assess together which approach is right for your project – technologically and economically.

Book a free consultation

Success stories
with measurable results

GUTEFRAGE.NET / HIGHFIVVE

Anyone looking for an app development agency will be delighted with Johnny Bytes. We held a workshop with gutefrage.net on the topic of apps and app SDKs and had a very in-depth and detailed exchange. The knowledge and experience that Johnny Bytes brings to the table is remarkable.

Nepomuk Seiler, Head of Engineering, gutefrage.net
Nepomuk Seiler
Head of Engineering, gutefrage.net
JUST HEALTH GMBH

Johnny Bytes was a complete game-changer for our digital health app. Their expertise is outstanding; they got up to speed in record time and drove our development forward with decisive technical insights. We absolutely recommend them for any complex app project.

Maximilian Roederstein, Co-Founder, JustHealth GmbH
Maximilian Roederstein
Co-Founder, JustHealth GmbH
EMPOWER GMBH

In the development of our software suite, we faced complex challenges. Johnny Bytes provided more than just strategic advice; they actively supported our development process and were decisive in its successful execution.

Stephan Kuhnert, Managing Director, empower GmbH
Stephan Kuhnert
Managing Director, empower GmbH
APOTHEKE LUX 99

We wanted more than just an off-the-shelf e-prescription app; we needed a solution perfectly tailored to our pharmacy's specific workflows. Johnny Bytes' expertise in digital health was clear as they understood and executed our vision in perfect detail. The result is our very own app, which is a tremendous asset for both our customers and our team. For anyone seeking a truly custom solution, you've come to the right place.

Tobias Loder, Inhaber, Apotheke LUX 99
Tobias Loder
Inhaber, Apotheke LUX 99
READFY

With Readfy, up to half a million users regularly read over 130,000 ebooks for free. Johnny Bytes took over the apps for iOS and Android from our previous nearshore partner and not only brought them and the backend up to date in a very short time, but also ensured that in-app sales increased by 500%.

Philipp Ortmaier, CEO, readfy GmbH
Philipp Ortmaier
CEO, readfy GmbH
PAGOPACE

We were already able to offer our customers good hardware with our payment ring. However, Johnny Bytes helped us to build the perfect complementary software to take our product to the next level. We were kept up to date at every stage of the app development and were able to make requests immediately. With the new app, we can also sell our rings in retail stores, as customers can link their rings directly to their payment card on their cell phone.

Steffen Kirilmaz, CEO, PAGOPACE GmbH
Steffen Kirilmaz
CEO, PAGOPACE GmbH
FIRST AVENUE

Johnny Bytes has taken over the development and support of our guest information system TIPPTHEK and migrated it to a modern and sustainable architecture in a very short time. This allows us to install TIPPTHEK in thousands of South Tyrolean accommodations and provide up to 35,000 tourists a day with personalized information about their accommodation and the surrounding area.

Michael Hölzl, CEO, First Avenue GmbH
Michael Hölzl
CEO, First Avenue GmbH
STAZZLE

An agile team for whom customer satisfaction is just as important as quality, the Johnny Bytes team understands communication and requirements, asks the right questions, has a sense of humor and adheres perfectly to schedules. A strong partner that we recommend without reservation. Thank you for your support!

Tasso Mitsarakis, Product Owner, stazzle
Tasso Mitsarakis
Product Owner, stazzle
KOOPERATIONEN MIT HOCHSCHULEN

Together with Johnny Bytes, FH Aachen regularly conducts practice-oriented research projects as part of the Digital Lab. Most recently, prototypes for Alexa skills and AI-supported tourism solutions were created in this context. These projects are always an enrichment for our students, the university and the company.

Prof. Dr. Mathias Eggert, FH Aachen
Prof. Dr. Mathias Eggert
FH Aachen

Start your app project
with Johnny Bytes

Discuss your app idea in a non-binding and free strategy meeting.

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