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VSTO Add-in Development Company

(We provide a wide range of client-oriented solutions using VSTO development services)

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Microsoft Office is a versatile platform in the world of technologies. Not only is it feature-rich, but it is also an expandable platform that caters to a variety of business needs. To power up business operations and efficiency, developers try to extend the functionalities of Microsoft Office for a rich user experience.

Office add-ins are used for extension of functions and alteration of office clients, for example, Microsoft Word, Microsoft Outlook, Microsoft Excel, Microsoft PowerPoint, and Office 365. Microsoft supports the modification of existing features and the creation of new features by using available tools and APIs.

There are different types of Office add-ins - to name a few - functionality extension in PowerPoint, Excel, and Word, creation of new objects in PowerPoint and Excel, extension of functions in Outlook add-ins, etc.

In general, there are two main technologies used for developing Office add-ins:

  • Develop add-in using Office JavaScript API

  • Develop add-in using Visual Studio Tools for Office (VSTO)

iFour Technolab, as a leading IT consuting company,employs the latest technologies to build superior systems for clients. Our professional team is experienced at using the latest tools for providing best solutions in the market. We use VSTO Add-ins for developing the best software for our clients.

Why VSTO development services are important?

(Adopt VSTO services and develop superior solutions for your business)

Visual Studio has gained huge importance in the sphere of .NET development. It offers great feature support that helps while creating document-level projects such as Windows Forms controls, document-designing, and data-binding by drag and drop facility, debugger, etc. With our years of experience, we have delivered effective solutions to a broad range of clients and fuelled many start-ups with our VSTO Add-in development services.

VSTO (Visual Studio Tools for Office) is a collection of development tools available as Visual Studio plug-ins and a runtime that enables Microsoft Office 2003 and subsequent versions of Office sources to host the .NET CLR (Common Language Runtime) and explore their capabilities via .NET.

Our high-end VSTO development services

(Acquire the desired results for your business with superior VSTO solutions)

iFour Technolab is a versatile VSTO Add-in development company in USA with vast experience in developing a broad range of solutions. For VSTO-based Office development, iFour uses the following templates

  • VSTO Add-ins and

  • Document-level customizations

VSTO Add-ins

Whatever features we create in VSTO Add-ins, are made available to the application itself, irrespective of the documents that are open. Our company builds solutions in such a way that the VSTO Add-ins run at a time when the associated application is started.

Document level customizations

Document-level customizations have an assembly which is associated with a single workbook, template or document in Microsoft Office Excel or Microsoft Office Word. Whenever we open the associated document, the assembly and customized features gets loaded.

Using various tools available in Visual Studio, our team can help you with document-level customizations and simplify your business concerns. The document which is customized is hosted as a design surface in Visual Studio. This makes it possible to design the document just by dragging and dropping controls onto it. iFour Technolab uses numerous features available in Visual Studio such as data binding, debugger and Windows Forms controls which result in robust and sustainable solutions for the client.

Being an experienced VSTO Add-in development company in USA, iFour offers these services:

  • VSTO Add-in, extension or plugin design and development for Microsoft Word

  • VSTO Add-in, extension or plugin design and development for Microsoft Outlook

  • VSTO Add-in, extension or plugin design and development for Microsoft Excel

  • VSTO Add-in, extension or plugin design and development for Microsoft Office 365

  • VSTO Add-in, extension or plugin design and development for Microsoft Office for Mac

  • VSTO Add-in, extension or plugin design and development for Microsoft Office for iPad

  • VSTO Add-in, extension or plugin maintenance and support

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Power up your business operations with VSTO development services

Key benefits of using our services:

  • High performance

  • Cost-effective

  • Business value

  • Quick results

  • Highly proficient team

  • Transparency

  • Adherence to deadlines

  • Competitive pricing and on-time delivery



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Our Agile approach


VSTO Add-in case study

iFour Technolab has been a reliable custom Addin development company with over ten years of market presence and incredible track record. Take a look at some of our work.

Our experienced Microsoft professionals have assisted clients of various domain verticals and helped them with Bespoke Addin development solutions tailored to suit their business requirements.

Connect with us now to hire Angular developers, Java developers and other diligent professionals and accomplish your business objectives.


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Industry expertise

Finance Finance


Custom Financial software development service provider

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Bespoke Healthcare software services and solutions

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Custom Aviation software development company

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Bespoke Legal software development service provider

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Bespoke Educational software development company

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Custom Fleet software services provider

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Hospitality software development services provider

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Transportation And Logistics

Custom Logistics software development services

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Custom Environmental software development services

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e-Commerce and Retail software solutions provider

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Bespoke Construction software development company

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Have a project idea?

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FAQs for VSTO development services

iFour Technolab is a Microsoft Certified Solutions Partner having experienced, vetted, and certified professionals. We have served over 15 industries with VSTO Add-in development services and assisted more than 50 startups. We believe in offering high-quality services on time adhering to strict privacy.

iFour Technolab works with goal-oriented perception and aims to deliver satisfying services to its clients. We have dexterous experts at all levels and departments. When the project development begins, it undertakes various departments to include in SDLC to assure project standard and perfection.

We provide you with a flexible pricing model to hire VSTO developers according to your needs. We generally have three pricing models i.e., dedicated team model, fixed-price model, hourly-based model. The pricing of each model depends on the developer’s skill-set requirement, experience level, and technology.

Our experts use VSTO, WPF, and JavaScript API to implement Office Addin solutions. In addition, we also keep focus on latest technologies to build superior systems.

Either Project manager, business analyst, or development team would be in direct communication with you depending on the development approach and processes you are comfortable with.

iFour Technolab is an inclusive hub for skilled developers proficient in different technology spheres such as .NET, Blockchain, Node.js, React, Angular, and other e-commerce platforms. Our experts can help you with custom software services using various technologies and fulfill your business needs.

Our VSTO experts examine and analyze your business requirements. We offer you the final budget and time estimation for your project development. A complete project implementation plan is shared with you during the first week of the project’s start.

We ensure your project idea remains secret with us. We make our VSTO professionals sign NDA to accomplish project security.

Our experts can help you with custom plugin development services for various platforms such as Microsoft Word, MS Outlook, Microsoft Excel, MS PowerPoint, and Office 365.

Our experts use Agile methodologies (SCRUM) while software project development.

Increase your business efficiency through VSTO Addin development.

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