Custom Mobile Development Services

KeyUA is a custom mobile app development company from Ukraine. Since 2008, we have been creating unique solutions for the needs of startups, small and medium-sized businesses, and large enterprises. Our mission is the top-notch and fast development of mobile apps which are characterized by high performance and reliable data protection.

What Is Included in Custom Mobile Development Services

At KeyUA we carefully study the needs of your business to create a competitive native or cross-platform software. During our 12 years of practice, we have built 50+ advanced applications for Android and iOS. Our team goes through the most important stages of providing custom mobile development services when working on each project: market analysis, design creation, development, testing, and release.
  • iOS App Development
  • Android App Development
  • Cross-Platform Development
  • App Porting
  • API Integration
  • Maintenance and Support

iOS App Development

If you need a product for iPhone, iPad, or Apple Watch, we guarantee you a quality solution. With KeyUA you can be sure that your app will work quickly and stably, while meeting all safety standards. Using native development tools, our developers create software that meets all the client's requirements.

  • 100% AppStore approval
  • Convenient payment method inside the application through Apple Pay
  • Full-stack team with sound experience in Swift & Objective-C

Android App Development

About 80% of the mobile devices on the market are occupied by Android smartphones. Increase your number of customers by developing an application to fit this platform. Our team is distinguished by the sound creation of software for smartphones, tablets, and wearables.

  • Smart home solutions
  • Google Wallet integration
  • Solid Java & Kotlin background

Cross-Platform Development

Do you need fast development for the most popular operating systems at an affordable price? Let us build you a cross-platform application. KeyUA has the ability to create top-notch and secure software that is compatible with the most used mobile platforms.

  • High performance
  • Convenient hybrid approach
  • Expertise in React Native, Flutter, Cordova & Xamarin.Forms

App Porting

If you have an Android application, and you want to adapt it for iOS or vice versa, the KeyUA team will work out a beneficial solution. Porting does not mean just copying the code, as mobile platforms have their differences. At KeyUA, we will make sure that your design looks great on all operating systems and the functionality is of the highest quality due to reliable SDK tools.

  • Fast delivery
  • User-friendly interface
  • Full specification compliance

API Integration

Make your application more attractive and interesting for customers by expanding its capabilities. Integration with third-party resources is a way to set up reliable payment gateways, make a real-time connection to Saas applications, and improve business processes due to ready-made solutions.

  • Reliable services providers
  • Quick integration
  • Extended range of resources

Maintenance and Support

Take care of maintaining your application so that it works perfectly even with the latest operating systems. Expand the functions, availability, and usability, including a bugfix from previous versions, an architecture upgrade, and the administration of existing solutions.

  • Use of the best practices
  • Innovative technologies
  • Matching market needs

Custom Mobile Development Solutions

It's easy to grow a business with the right mobile solution. We are engaged in the custom development of mobile apps that fully meet the needs of your company.
Building an App From Scratch
At KeyUA, we build applications of any complexity, creating reliable and scalable solutions. All that is required of you is to show us the idea, and we will take care of its high-quality implementation.
App Maintenance
If you already have a working product and you are looking for someone who can absolutely support it or fix bugs, we will be happy to help you! Our developers will evaluate your application and provide solutions to improving its performance.
UI/UX Design
Design is not just what the application looks like. This is what motivates users to devote more time to the application and make purchases. Make sure your application is intuitive, and its elements call to action.
Strategy & Features
A successful application is a collaboration between business analysts and product managers. The development of product concepts and the identification of the main problems, limitations, and features are definitely what you need to be highly competitive.

Why Key UA is the Best in Supporting Your Business

As a reliable IT company, we provide mobile software development services for various areas, including applications for business, entertainment, healthcare, education, sports, music, photo processing, and more. We use innovative technologies and carefully test each function in order to deliver a truly perfect product.

Development of fast and intuitive mobile apps

Strategic consulting

Proactive approach

Experienced mobile app developers

Full focus on business needs

Protection against security threats

Solid testing background

Transparent app building process

Project support & maintenance

Quality risk management

Full technology stack

Fast time to market


years of practice in custom mobile application development


experienced team members


successfully delivered mobile apps


data security

Contact Us

Project Steps

We adhere to a clear development process and Agile methodology so that the application is delivered quickly and efficiently.

Getting Requirements

We go over the requirements and process them in order to determine all the goals of the project. Typically, the client provides us with a specification in the form of a document, but if this is difficult for you, we can consult by phone to determine all your wishes. After which, our specialists will prepare all the necessary papers. Before proceeding to the next step, we discuss all the features and nuances of the future app in detail with the client.


Contract Signing

We discuss the pricing policy with the client, then sign all the documents necessary for development, including a non-disclosure agreement.



Our IT experts hold a meeting to determine which technology stack is best suited for the building of the project. We also draw up a plan for the implementation of tasks, breaking everything down into iterations.



KeyUA’s creative experts develop mockups for the future application on the announced operating systems. We carefully draw each layout, as the design directly affects the behavior of the user. Proper mockups motivate users to make more purchases, help in navigation, and increase the number of customers.


Development Stage

This is when your idea turns into reality. KeyUA programmers begin native or cross-platform development, depending on your needs and peculiarities.



We test the product to ensure that its functionality meets specifications. At this stage, the customer can also check the application and, if they want, make changes.



At this stage, we deploy the ready-made application to the AppStore and Google Play.



KeyUA marketing specialists develop effective and quick strategies to promote the product in the market and increase its online popularity.



After launching the application on the market, our developers continue to support and update the product in order to maintain its popularity.

Examples of Our Successful Projects

At KeyUA we provide services for beginner entrepreneurs, federal agencies, corporate clients, and large businesses. Over the 12 years, we have been delivering quality web apps to the market, most of which we support until now.

Clients Speak About Us

Our team is fully focused on client satisfaction. A long and reliable relationship is the key to prosperity.

Frequently Asked Questions

Let's clarify a few more important questions regarding mobile app development.
What is a custom app development?

Custom development is the creation of an application from scratch that fully meets the goals and needs of your business. This is a great opportunity to expand sales of your goods and services, get new customers, and achieve a significant competitive advantage.

How long does it take to develop a custom mobile app?

The development time is different for each project since the requirements for the application can vary greatly depending on the needs of the business. In general, on average, building an application takes at least 6-8 weeks.

Will I get the copyright of source code?

Of course. In accordance with the contracts that we sign with the customer, they are the owner of the code and intellectual property of the product. You will have access to the repository with source codes and other technical aspects of the project.

Get in Contact With Our Experts

Want to get an accurate estimate for your project? Contact our experts and we will provide you with a free consultation and technical recommendations.
Manager Daria Maltseva

Daria Maltseva

Product Manager

Contact Now