Custom API Development

API is a set of specific programs and tools for creating turnkey solutions in a simple language. The development of API plays an important role in doing business, as it is a reliable element in the interaction of internal and external systems and devices. Since 2008, KeyUA has been building reliable API solutions for both small and large enterprises.

What is Included in Custom API Development Services

In today's world, there are no web or mobile isolated applications. All of them have integration with third-party resources through API. This allows you to significantly expand the capabilities of the software with minimal costs and time. At KeyUA we have been developing, integrating, and maintaining APIs for over 12 years to help businesses of all sizes expand their opportunities.
  • API Development for Mobile Applications
  • Web API Development
  • API Development for Cloud Computing
  • Third-party App Integration
  • API Support & Maintenance Services
  • API Testing Services
  • API Consulting

API Development for Mobile Applications

Nowadays many companies prefer to create their own API due to the significant increase in the use of mobile applications. Our team provides various options for custom API development, including:

  • GPS usage to determine the location
  • Data verification
  • Calendar management, etc

Web API Development

Web API acts as an interface for web servers & web browsers and is also used by the HTTP-service. So the compatibility of all devices can be achieved thanks to top-notch API development. At KeyUA we adhere to a reliable approach, involving ROA and RESTful API development.

  • Device status information
  • Access to information stored on devices
  • Extended access for web applications

API Development for Cloud Computing

Integrate your applications directly into the cloud thanks to the appropriate API. At KeyUA, we develop various cross-platform solutions to expand the capabilities of your product through cloud technologies.

  • Joint access to documents
  • Photo and video storage
  • Getting access to lots of cloud resources from various providers

Third-party App Integration

Our company also provides integration services with third-party resources. Let your application serve even more customers through integration with maps, social networks, payment gateways, web services, and so on.

  • Oracle web services integration
  • Google Maps, Yahoo, Facebook, Twitter, etc. linking
  • PayPal, Skrill, Amazon integration, etc

API Support & Maintenance Services

At KeyUA we continue cooperation even after the range of tasks are completed. Our experts also support API services to make sure that they work correctly. We develop effective solutions to help your business always stay on top.

  • Reviewing and maintaining interaction
  • Code update and optimization
  • Checking device compatibility and resolving related issues

API Testing Services

Our highest priority is quality development that fully meets the requirements and business goals. That's why our tech talents carefully test all the functionality that we produce.

  • Services integration verification
  • Boundary value analysis
  • Division on equivalence classes

API Consulting

The KeyUA team will help you to fully investigate all processes of an app and analyze the logic of the product. Our experts will develop a clear plan for you regarding proper integration and service improvements.

  • The right choice of the necessary API
  • Careful code analysis
  • The resolution of all integration problems

Custom API Development Solutions

Our company successfully builds high-performance and safe APIs for various industries and businesses of any size. KeyUA developers also demonstrate vast experience in API integration services.
High-Performance API Development
All APIs vary in size and provide extremely different services. Our team writes clean and qualitative code in order to provide a high-performance and quick response from APIs of any size and complexity.
API Customization
We carefully review all the requirements to create a quality API that meets all business needs. Our team collects the full specification and carefully studies it in order to have a deep understanding of how the system should work.
API Specialists
Our team creates API solutions for new projects that we are working on and for already working platforms built by other developers. We provide a wide range of services that satisfy even the most demanding customers.

Why KeyUA is the Best in Supporting Your Business

Our expert team prepares and implements solutions of any complexity in the shortest possible time. It is important for us that the developed systems fully meet customer requirements. Here are extra bonuses that you can get by working with us:

Quick turnaround time

Solid technical consultation

Secure integration with payment systems

Django REST Framework Experts

Product maintenance after delivery

On-time project delivery

Development of complex websites and mobile apps

Maintaining high system performance

Production of complex and unique solutions

Experienced team

Development of solutions for various industries

NDA Compliance


years of expertise in API development & integration


experienced team members


successfully delivered projects


data security

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Project Steps

And now let's take a closer look at the process of creating API, which our team performs.


We collect all the requirements for the system and study the wishes of the customer to determine the upcoming scope of tasks.



At this stage, our developers select the most appropriate technologies that best meet the objectives of the project. We also plan the main steps of API to creation.



We develop the expected product, based on the requirements and the selected technology for API building.



Once the development process is completed, quality assurance specialists will begin to thoroughly test the system’s functionality and integration features. In case of any errors or bugs, we will immediately proceed to their elimination.



After the testing process is over and we have made sure that the platform fully meets the business requirements, our developers will deploy the ready-made functionality in a living environment.

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

At KeyUA, it pleases us when we manage to fully satisfy the business needs of our customers.

Frequently Asked Questions

If you need our help, you can contact our specialists and get a free estimate of your project. We have also collected the main questions that customers ask us to help you better understand the services we offer. If you need our help, you can contact our specialists and get a free estimate of your project. We have also collected the main questions that customers ask us to help you better understand the services we offer.
How much do you charge for your API development services?

The price varies depending on project requirements. First, we must study your conditions and wishes, after which our team will be able to draw up a project plan and give a more accurate assessment of the time and cost of implementation.

Can you build the APIs for my specific needs?

Of course. We will create APIs of any complexity to fully satisfy the needs of your business.

Will I be able to work directly with the development team?

Our development process is completely transparent. At any time, you can contact any member of the development team to get an update on the current status of the project. We can also plan daily or weekly calls between you and the team, so that you can constantly be up to date with the latest project execution news.

What industries do you cover with API development services?

KeyUA provides services for various industries and businesses of any size. Regardless of whether you want to release a product for internal use of your enterprise or to build a commercial project, we are always happy to provide you with solutions that fully meet your requirements.

Contact Our Experts Right Now

We are here to help you develop your ideas and grow your business! Contact our experts for more information.
Manager Daria Maltseva

Daria Maltseva

Product Manager

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