Desktop Application Development

PS3G provides desktop application development for organizations of every size: Windows applications built in .NET with WPF or WinUI, cross-platform desktop apps with .NET MAUI or Electron, and modernization of the WinForms, VB6, Access and classic Delphi applications that still run parts of many businesses. Whether you are a founder shipping a tool that must work offline, an operations lead whose team lives in an aging Windows program, or an IT director with a legacy desktop application nobody dares to change, we build or modernize the software and connect it to your cloud, database and identity systems.

Desktop application development: what we build and for whom

Web applications are the default for most business software, and we build plenty of them. Desktop software still wins in specific cases: work that must continue without a network, heavy use of local hardware such as scanners, instruments, label printers or cameras, applications that process large local files, high-performance user interfaces for power users, and environments where policy keeps data on the machine. Point-of-sale, laboratory, engineering, medical-device companion, field data capture and back-office processing tools are typical.

As a desktop software development company that also builds web and mobile applications, we start with the question of whether desktop is right, and we often recommend a hybrid: a desktop client for the offline or hardware-bound work and a web back end for everything shared. We build software only; the PCs, scanners, printers and other devices are yours to choose, and we do not sell or support hardware.

What the service covers

Area	Typical work	What you receive
Windows application development	New applications in C# on .NET with WPF or WinUI 3; MVVM architecture; Windows integration (printing, file system, services, registry, COM where unavoidable)	A signed, installable application with source code, tests and documentation
WPF development	Data-heavy user interfaces, custom controls, charting, theming, accessibility	A maintainable WPF front end with a component library
Cross-platform desktop	.NET MAUI or Avalonia for Windows and macOS from one C# codebase; Electron with React or Angular for web-based teams	Builds for each platform from one codebase and one pipeline
Electron app development	Desktop wrappers and full apps around web technology; native menus, file access, auto-update, notifications	Packaged, signed apps for Windows, macOS and Linux with update infrastructure
Legacy desktop application modernization	WinForms, VB6, Access, Delphi and .NET Framework applications: assessment, incremental migration to .NET 8 or later, UI replacement, database move, or re-platforming to web	A modernization plan and a working application at each stage
Offline and sync	Local SQLite or LiteDB storage, conflict handling, background synchronization with a cloud API	Reliable offline operation and a documented sync protocol
Hardware and device integration	Barcode scanners, label and receipt printers, scales, serial and USB instruments, cameras, card readers	Tested device drivers and abstractions so devices can be swapped
Packaging and deployment	MSIX or MSI installers, code signing, auto-update, Intune or group policy deployment, Microsoft Store where wanted	An installer, an update channel and a release process

How we work

Process

1. Discovery. Who uses the application, on what machines, with what devices and under what network conditions. For modernization, we also read the existing code and database and list what the application does that nobody wrote down.
2. Architecture. Desktop, web or hybrid; framework choice; offline strategy; how the app authenticates (Entra ID, Active Directory or your identity provider) and talks to the back end.
3. Build in increments. A working build early, with the core workflow and device integration first because they carry the risk. Each increment is installable and tested by our testing center of excellence on the target Windows or macOS versions.
4. Package and roll out. Signed installers, an update mechanism, deployment through your management tooling, and a pilot group before general release.
5. Maintain. Operating-system updates, framework updates and feature changes under a support arrangement, or a documented handover.

Team

A .NET or Electron lead, one or more developers, a UX designer for desktop interaction patterns, and a QA engineer with the target machines and devices. Modernization projects add an engineer who is comfortable in the legacy codebase. The team sits in Wilmington, Delaware and in our India delivery center.

Stack choices

For Windows-only applications we recommend .NET with WPF for data-dense business interfaces and WinUI 3 for a modern Windows look. For Windows and macOS from one codebase, .NET MAUI or Avalonia keeps a C# team productive; Electron is the better choice when your team already works in React or Angular and the app is close to a web application. Local data lives in SQLite, and the back end is an ASP.NET Core API through our .NET development practice. For the long term we favor frameworks Microsoft actively supports, and we check the current lifecycle pages with you when choosing versions.

Ask for a modernization assessment of your existing desktop application.

Where this fits with the rest of your systems

Most desktop applications today are clients of a cloud system. The database behind them moves to Azure SQL or PostgreSQL, the business logic moves into an API, and the desktop app becomes the part that handles offline work and local devices. That is the pattern we use in application modernization when the application must stay desktop, and in .NET migration and modernization when a .NET Framework application needs to reach a supported runtime.

After launch the application needs someone to handle operating-system and framework updates, certificate renewals and feature requests, which is what our software development and maintenance arrangements cover. Where a companion mobile app is needed for the same users, our mobile team builds it against the same API.

Examples by organization size

• A founder-led company with a specialized tool for a trade, a lab or a clinic that must work offline and drive a local device. We build a .NET MAUI or WPF application with SQLite storage and cloud sync, package it with auto-update, and hand over the code. Fixed scope.
• A growing company running operations on a WinForms application built years ago on .NET Framework with a SQL Server database. We assess it, move it to .NET 8 or later in stages, replace the most-used screens with WPF, move the database to Azure SQL, and keep the team working throughout. Support continues under a monthly arrangement.
• A department inside a larger organization with a VB6 or Access application that still runs a regulated process. We document what it does, rebuild it as a desktop client with a .NET API and a proper database, integrate with the corporate identity provider, and deploy through the organization’s device management inside its security and change-control rules.

Engagement models

• Fixed-scope project. A new application, a modernization stage or a device integration with a defined deliverable list and a fixed quote.
• Dedicated team or staff augmentation. WPF, .NET MAUI or Electron developers inside your team on a monthly basis.
• Managed services. We maintain, update and support the application and its back end under defined SLAs.
• Advisory. A desktop-versus-web assessment, a legacy application review, or a framework and roadmap recommendation.

How we start: a first conversation, a short assessment, a written proposal.

Why PS3G for desktop app development

More than ten years on the Microsoft stack, with engineers certified on Microsoft and open-source technologies and a team across a US headquarters in Wilmington, Delaware and an India delivery center. We build and run our own products, including our HIPAA-compliant EHR and telehealth platform, DocVilla, so applications that handle regulated data get the security and audit practices we use ourselves. Our testing center of excellence tests on the actual Windows and macOS versions and devices your users have, which is where desktop projects usually fail when testing is skipped.

Related services

• .NET development: the C# teams and APIs behind our desktop applications.
• Application modernization: incremental paths off legacy desktop systems.
• .NET migration and modernization: .NET Framework to .NET 8 and later.
• Software development and maintenance: keeping the application current after launch.
• Mobile app development: companion apps on the same back end.
• All services: everything we build, modernize and run.

Frequently asked questions

Should we build a desktop application or a web application?

Build desktop when the work must continue offline, when the application drives local devices such as scanners, printers or instruments, when it processes large local files, or when policy keeps data on the machine. Build web when users are spread across devices and locations and the work is online. Many organizations need a hybrid: a desktop client for the offline and device-bound part and a web application for the rest, sharing one API.

WPF, WinUI, .NET MAUI or Electron: which should we use?

WPF for data-heavy Windows business applications with a mature ecosystem. WinUI 3 for a modern Windows interface on current versions. .NET MAUI or Avalonia when you need Windows and macOS from one C# codebase. Electron when your team works in React or Angular and the app is close to a web application. We recommend after looking at your users, your team and the devices involved.

Can you modernize our old WinForms, VB6 or Access application?

Yes. We assess the code, database and the undocumented behavior, then choose between incremental migration (moving to a supported .NET runtime and replacing screens over time), a rebuild as a desktop client with a modern API, or re-platforming to web where desktop is no longer needed. The application keeps working during the change, and the data is migrated and reconciled rather than left behind.

How do you handle offline use and synchronization?

Data is stored locally in SQLite or a similar embedded database, the application works fully without a connection, and a background process synchronizes with the cloud API when connectivity returns. Conflicts are handled by rules agreed with you, such as last-write-wins for some records and a review queue for others. The sync protocol is documented and tested under poor-network conditions.

How are updates delivered to users’ machines?

We package the application as a signed MSIX or MSI installer with an auto-update channel, or as a signed Electron package with its updater, and deploy through Intune, group policy or your management tooling. A pilot group receives each release first. Code signing certificates are yours, and we document the renewal process so releases do not stall.

Do you sell or support the hardware the application uses?

No. We build and test the software against the scanners, printers, instruments and PCs you choose, and we design device abstractions so a model can be swapped later. Purchasing, warranty and hardware support stay with your vendor. We will advise on compatibility during design so the devices you buy work with the application.