How AccelOne built and evolved Trimble's mobile construction management platform, delivering real-time visibility, 4% cost savings, and a future-ready codebase.
In brief: AccelOne developed Project Site, a mobile extension of Trimble's e-Builder platform for construction project management. The app delivers real-time updates, document sharing, scheduling, budgeting, and field reports to distributed construction teams on iOS and Android. Built initially in Xamarin, then migrated to .NET MAUI for improved performance and long-term maintainability. Includes a custom PDF editing library. Key outcomes: 100% project visibility, up to 4% cost savings, reduced project risk, and increased team productivity.
100%
Project visibility for all stakeholders
Up to 4%
Cost savings through financial control
Xamarin → MAUI
Full framework migration completed
Custom
PDF editing library built from scratch
Global
Client: Trimble, global construction tech leader
About Trimble and the construction management problem
Trimble is a global leader in construction technology, providing enterprise software, hardware, and positioning systems used across the construction, geospatial, and transportation industries. Their e-Builder platform is one of the leading enterprise construction program management systems for capital project owners.
Construction projects are inherently distributed: project managers, site engineers, contractors, and executives rarely work from the same location. Fragmented tools, disconnected emails, local spreadsheets, separate document systems, create information gaps that cause delays, errors, and budget overruns.
Trimble needed a mobile app that brought the same visibility and control of e-Builder to field teams and stakeholders anywhere, not a simplified read-only view, but a genuine extension that enabled real-time updates, document management, and financial oversight from any device.
Why does construction project management fail without mobile?
Project data scattered across emails, spreadsheets, and disconnected tools creates gaps, different teams working from different versions of the truth.
When field teams can't access or update project information in real time, decisions wait for the next meeting or the next time someone is at their desk.
Without real-time financial visibility across all stakeholders, cost issues are identified late, after they've become expensive problems.
Without a centralized system, tracking who approved what, when, and based on which document version becomes a manual and error-prone process.
What does Project Site do?
Project Site is an all-in-one construction management platform on mobile, designed to give every project stakeholder the same visibility and control that e-Builder provides from the desktop, available from anywhere on iOS or Android.
All project data stays current for every stakeholder, field teams and executives see the same information, instantly.
Share, review, and annotate project documents, including a custom-built PDF editing library for precise document management.
View and manage project timelines from mobile, keeping distributed teams aligned on milestones and deadlines.
Real-time financial visibility for project managers, enabling proactive cost control rather than reactive budget reviews.
Site teams submit and access field reports directly from mobile, eliminating the delay and transcription errors of paper-to-system entry.
All project information in a single view, status, budgets, documents, and reports accessible to every stakeholder from one interface.
Why did AccelOne migrate Project Site from Xamarin to .NET MAUI?
The migration from Xamarin to .NET MAUI was not optional, it was a necessary evolution. Microsoft ended mainstream support for Xamarin in May 2024, making it critical that enterprise apps built on Xamarin move to MAUI before the framework became unsupported.
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Mainstream support ended May 2024
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Separate project structures for iOS and Android
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Older .NET runtime with limitations
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Reduced long-term maintainability
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No future Microsoft framework updates
✔ Long-term Microsoft support and updates
✔ Unified project structure, iOS and Android from one codebase
✔ Modern .NET runtime with improved performance
✔ Better code reusability across platforms
✔ Foundation for future feature development
Beyond the support lifecycle, MAUI offers a genuinely improved architecture: a unified project structure replaces Xamarin's separate iOS and Android projects, the modern .NET runtime improves app performance, and greater code reusability reduces the long-term cost of maintaining and extending the application.
What were the key technical challenges?
Trimble's design requirements were precise, and the available third-party libraries didn't meet them. AccelOne minimized reliance on third-party libraries and built custom components instead, ensuring every UI element matched the specification without compromise.
This required significant engineering effort but produced a higher-quality result than adapting a library's behavior to fit requirements it wasn't designed for.
PDF documents are central to construction project management, contracts, drawings, inspection reports, and compliance documents. No existing library met Trimble's exact requirements for how PDF editing should work within Project Site's interface.
AccelOne built a custom PDF editing library from scratch, tailored to the specific design and functional requirements of the application. This was one of the most technically demanding components of the project.
Migrating a production app from Xamarin to MAUI is not a straightforward upgrade, it requires restructuring the project architecture, updating API calls where MAUI and Xamarin differ, adapting custom renderers to MAUI's handler architecture, and retesting the full application across both platforms.
AccelOne executed this migration while maintaining all existing functionality and improving performance, requiring meticulous planning to avoid regressions in a live enterprise product.
Technology stack
.NET MAUI (migrated from Xamarin), iOS and Android from a single codebase.
C#, shared business logic and UI across platforms.
Custom-built library, tailored to exact design specifications.
Trimble e-Builder, mobile extension of the enterprise platform.
Kanban, dashboard-based visibility into all development stages.
Regular retrospectives and continuous process refinement.
What were the results?
100%
Real-time collaboration and complete project visibility for all stakeholders, from field teams to executives, through a single, centralized mobile platform.
Up to 4%
Cost savings through improved financial control and data-driven decision-making. Better budget visibility means issues are caught earlier and cost overruns prevented.
Improved data strategies enabled more informed decision-making at every project stage, reducing the risk of delays, errors, and scope changes that stem from incomplete information.
Streamlined communication and centralized information access across distributed teams enabled tighter project control and measurable efficiency gains in daily project operations.
Beyond the individual project metrics, Project Site strengthened Trimble's competitive position in the construction technology sector, offering a comprehensive mobile solution that drives transparency, data-driven execution, and cost savings across capital construction programs.
Frequently asked questions
What is Project Site and how does it extend Trimble's e-Builder platform?
Project Site is a mobile construction project management application built by AccelOne for Trimble, designed as a mobile extension of Trimble's e-Builder enterprise platform. It brings real-time project updates, document sharing, scheduling, budgeting, and field reporting to iOS and Android devices, giving distributed field teams and stakeholders the same visibility and control as e-Builder from any location.
Why did AccelOne migrate Project Site from Xamarin to .NET MAUI?
Microsoft ended mainstream support for Xamarin in May 2024, replacing it with .NET MAUI. Migrating Project Site to MAUI was both a strategic necessity and a technical upgrade: MAUI offers improved performance, better maintainability, greater code reusability across iOS and Android, and long-term platform support. The migration ensured the app would continue receiving framework updates and security support, and positioned the codebase for future development.
What is .NET MAUI and why does it matter for cross-platform mobile apps?
.NET MAUI (Multi-platform App UI) is Microsoft's cross-platform framework for building iOS, Android, macOS, and Windows applications from a single C# codebase. It is the successor to Xamarin.Forms, providing improved architecture, better performance, a unified project structure, and modern .NET runtime support. For enterprise apps like Project Site, MAUI reduces development and maintenance overhead by sharing business logic, UI code, and platform integrations across iOS and Android from one codebase.
What were the key results of Project Site for construction management?
Project Site delivered four measurable outcomes: 100% project visibility for all stakeholders through real-time data access, up to 4% cost savings through improved financial control, reduced project risk through better information strategies and early issue detection, and increased productivity across distributed teams through streamlined communication and centralized information access.
Why does construction project management need a dedicated mobile app?
Construction projects involve distributed teams, site workers, project managers, contractors, and executives, who need access to the same information but rarely work from the same location. Without mobile access, project data is fragmented across disconnected tools, causing delays, errors, and budget overruns. A mobile app like Project Site centralizes schedules, budgets, documents, and field reports in one place, giving every stakeholder real-time visibility from any device.
Why did AccelOne build a custom PDF editing library for Project Site?
PDF documents are central to construction project management, contracts, drawings, inspection reports, and compliance documents all live in PDF format. Existing third-party PDF libraries did not meet Trimble's exact design specifications. Rather than conforming the design to a library's constraints, AccelOne built a custom PDF editing library tailored to the specific requirements, ensuring the document editing experience matched the app's standards exactly.