Talk to us about your contractor app.
A free, no-obligation half-hour introductory call. We listen to your site workflow, ask about what is getting stuck now and which integrations need to be built, and give you direction you can actually use.
Service · App development
Custom contractor app for the building site and back office.
A custom app for main contractors, subcontractors and renovation firms that want work order workflows, time registration, photo reporting and project coordination together in one environment: working on site, including offline, and integrated with your existing construction administration.
A contractor app is more than a digital work order.
A contractor's work takes place in two places at once: on site and in the office. A site manager takes photos of progress, a planner schedules subcontractors, a project manager keeps an eye on quality, and in the office everything has to be recorded properly in the project accounts for invoicing, cost control and handover. One app should bridge that gap, without your people having to retype things by hand into a spreadsheet or an email in between.
We build these custom apps for construction firms who find that off-the-shelf packages don't fit. Both installation companies and main contractors, subcontractors, renovation and restoration firms find that their specific workflow doesn't fit into a commodity app, and that is exactly where bespoke development makes the difference. Mid-market players (not BAM or Heijmans, which have their own platforms, but the whole field beneath them) almost always find room for their own solution that suits their process.
A contractor app is deliberately broader than a field service app: not just an engineer handling something on location, but a whole project team working for days, weeks or months on a single site, with more subcontractors, more documents and stricter handover requirements. Compared with software for a specialist demolition company, the contractor app covers general building work: main contractors and subcontractors, small to medium-sized, project-based rather than strictly asbestos- or dismantling-focused.
Three flavours of contractor app.
Depending on your type of business and how deeply the app needs to embed in your workflow. We'll advise which direction suits you in the first conversation.
Work order and timesheet app
For smaller construction firms and subcontractors who want to digitise their work order process. Photos at start and handover, client signature, material usage and hours per project, sent directly from the app to your accounts. Works offline on site and syncs as soon as there is signal again.
Digital work orderHours per projectPhoto flowClient signature
Project app for mid-market contractors
For construction firms with 10–50 employees running several projects in parallel. Site preparation, planning, material orders with Praxis Pro, Mastermate or Technische Unie, V&G checklists and handover, all linked together and integrated with your construction administration or time registration system.
Project foldersSchedulingMaterial orderingV&G & toolbox talks
Cascade app for main contractors
For main contractors working with twenty or more subcontractors on larger projects. Cascade planning, claims, quality sign-off per discipline, BIM integration for site managers, a client portal for clients and housing associations, and CO2 and VCA reporting for tendering bodies that require it.
If you remediate soil, you work under an accreditation and the environmental supervision is recorded separately. See the app for soil remediation under BRL SIKB 7000.
Subcontractor coordinationBIM integrationClient portalCO2 & VCA
What a contractor app typically does.
One app typically brings together a set of work processes that sit separately in standard packages. For your site managers, planners and project managers, it becomes one streamlined flow.
- Job ticket and order handlingPhotos at start and handover, customer signature on screen, material use and hours on one screen, linked directly to the correct project line.
- Timesheets by project and by locationSite managers log their hours against the correct project line, optionally with GPS confirmation that they were actually on site, useful for invoicing and collective labour agreement (CAO) administration.
- Materials and ordering flowOrder directly from the app with wholesalers such as Praxis Pro, Hornbach Pro, Mastermate or Technische Unie, with automatic allocation to the correct project cost centre.
- Photo and video reportingA structured photo flow for start, progress and handover, with automatic tagging per project and per element, which is useful for variation discussions later on.
- Safety: H&S plans, risk assessments and toolbox talksToolbox talk checklists, review of the health and safety plan on site, follow-up of risk assessment actions and incident reporting straight from the screen.
- Offline project foldersDrawings, permits, contracts and specifications available on site, even without signal, a persistent problem on new-build locations.
- Client and principal communicationShort chat, handover sign-off, and confirmation of additional and omitted work, all held against the right project rather than scattered across WhatsApp and email.
- Subcontractor coordinationScheduling for subcontractors, approval of invoice slips, claims and quality acceptance, feeding back into main contractor administration and chain liability evidence.
- Back-office integrationIntegration with construction administration packages such as Itannex, Bouw7, Cohga, KYP Project or Builder, and with general ERP systems such as AFAS or Exact for finance.
When bespoke development is the right choice.
We don't replace Itannex or Bouw7 for standard functions. Custom development makes sense when your work differs from what those packages handle out of the box. If you recognise any of these patterns, a conversation can help.
Mobile-first job ticket
A standard app doesn't fit your workflow
Your site crews want to see as few fields as possible, in a specific order, with fields that matter to your trade. That is exactly what standard packages struggle with. Custom development lets us design the UX around how your people actually work.
Industry-specific
Restoration, listed buildings or civil engineering
Restoration firms, listed-building contractors and civil engineering contractors have reporting requirements, handover protocols and quality checklists that aren't part of mainstream construction admin software. A custom app makes that discipline-specific workflow genuinely practical.
Deep integration
Integrating more than one system
Your construction administration, wholesaler portal, accountancy package and planning tool need to work together as one connected chain. We build that integration layer so your people don't have to retype data manually across four screens.
Customer portal
Clients with multiple projects
Housing associations, property owners and public-sector clients want to see their ongoing projects in one place: progress, photos, handover and finances. Your own client portal sets you apart in tenders.
AI-augmented
Photo recognition and progress detection
Automatically counting materials from a stock photo, detecting progress by comparing photos over time, or automatically flagging quality issues. These AI components aren't part of standard packages but can be integrated into custom development.
Cascade coordination
A main contractor with 20+ subcontractors
When you manage twenty or more subcontractors at once, the chain administration becomes a job in itself. A dedicated project management layer keeps scheduling, claims and approvals in a single source of truth, usable as evidence for chain liability.
How a contractor app project works.
1
Introduction
A conversation in which we understand which workflows the app needs to cover, what type of work you do, which construction administration you use and where things currently get stuck.
2
Site interviews and scope
We talk with site managers, planners and a project manager, often literally on a construction site. At the end you have a concrete scope, a first screen flow and a realistic plan per sprint.
3
Building in sprints
A working build every two weeks that your people actually test on a real site, not just in a meeting room. We first get the job ticket workflow working, then scheduling, materials and reporting.
4
Back-office integration
Integration with your construction administration (Itannex, Bouw7, Cohga, KYP, Builder) or general ERP (AFAS, Exact). At the end, time registration and project cost codes are automatically in your administration.
5
Rollout and management
Phased rollout, with training for key users and short video instructions for site managers. Followed by ongoing management: security patches, App Store and Play Store updates, and further development based on what practice teaches us.
Not yet sure about a large project?
Test your idea first: a working prototype in 1 day
With OneDayBuild, we turn your idea into something tangible in one day for €1,150, so you can see whether further development is worth the investment. Decide to go ahead with the full build? Then we credit the full cost.
Explore OneDayBuild →Compliance and regulation in construction.
Construction is heavily regulated, and getting more so. A good contractor app documents that you meet the applicable requirements — not as after-the-fact reporting, but built straight into the workflow on site.
Security
Health and safety, V&G and RI&E
Make the Health and Safety Plan visible on site, follow up on RI&E actions, use toolbox meeting checklists and report incidents directly from the app. During an inspection, you have the evidence ready in a few taps.
VCA
Safety Checklist for Contractors (VCA)
For clients who require VCA certification, we can build the relevant inspection checklists, certificate registration and logging directly into the app. An audit trail per project, per employee and per subcontractor.
Building Decree and NEN
Building Decree (Bbl) and NEN standards
Since the Environment and Planning Act, you work under the Building Works in the Living Environment Decree (Bbl). Specific NEN construction standards, such as the NEN 6700 series or NEN 2580, can be built into handover checklists and bespoke quality protocols.
Chain liability
Chain liability legislation
When working with subcontractors, you carry liability for their payroll tax and social security contributions. The app records who did which work, and when, with how many hours — useful during a chain audit by the Tax and Customs Administration.
CO2 Performance Ladder
Reporting for clients
Clients, particularly in the public sector, ask for CO2 reporting under the CO2 Performance Ladder. Fuel, plant and material data from the app feed your reporting directly — no separate spreadsheet administration afterwards.
GDPR
Client data and photos on site
Site photos can contain people, client data sits in handover documents, and timesheet data is personal data. The app is designed with privacy by design: role-based access, retention settings and, where needed, automatic blurring of people in work photos.
Packages we run into.
Many construction firms already use an existing construction administration or project package. A bespoke app does not replace that, but wraps its own layer around what the package does not do itself.
Itannex, Bouw7, Cohga
The common Dutch packages for project administration, time registration and invoice flow in construction. Strong on basic administration, limited in mobile UX and sector-specific workflows. We connect our custom app via available APIs or structured export and import.
ItannexBouw7CohgaAdlatus
KYP Project, Builder, BIM 360
Planning packages such as KYP Project and Builder are popular for planning medium-sized construction projects. For larger international clients and projects with demanding BIM requirements, you are more likely to work with Procore or Autodesk BIM 360. We make sure your site managers see that planning or BIM data in the right screen flow on site.
KYP ProjectBuilderBIM 360Procore
AFAS, Exact and specific functions
For finance, payroll and general ERP functions, AFAS or Exact is often used. In addition, function-specific packages such as Sigma, Cordel or Planrad. We do not rebuild what already works well here, but we do build the mobile layer and the specific workflows your site teams use every day, and connect that chain to your financial administration.
AFASExactSigmaCordel
Frequently asked questions.
What contractors and construction firms usually want to know before we start.
Do you replace Itannex, Bouw7 or another construction administration package?
Not for commodity functions such as project administration, invoicing flows or basic time tracking. Those packages do what they do well and cost less than custom software. We build a custom app on top of them or alongside them, for the part that makes your workflow specific, and connect it to your existing package via API or CSV export.
Does the app work on the building site without signal?
Yes. Offline mode is almost always essential in our designs, since new-build sites and restoration projects typically have poor 4G or 5G coverage. Work orders, photos, hours and checklists are stored locally on the device and sync as soon as signal returns. Conflict resolution is built into the design.
How do you integrate with our construction administration and ERP?
Through available APIs where the supplier offers them (Bouw7, KYP, AFAS, Exact and most modern packages generally do), or through structured export and import where that is the only route. In the first sprint we investigate which approach is realistic for your stack, and then build a stable synchronisation layer.
How do you handle the subcontractor workflow and chain liability?
Subcontractors receive their own role in the app, with access only to their own project lines. Work order approval, invoice approval, quality sign-off and hours overviews are recorded in an audit log, which is useful during a chain inspection under the Dutch Chain Liability Act (Wet ketenaansprakelijkheid) and as evidence for your accountant.
Can you create custom quality and handover checklists?
Yes, that is almost always part of the project. NEN construction standards, Bouwbesluit/Bbl components, VCA checklists or your own quality standard are set up as a digital checklist. On handover the client can sign on screen, and the document is automatically linked to the project file.
What can you do with AI and photo recognition?
Labelling photos by component, detecting progress by comparing photos over time, automatically counting materials from a stock photo, or raising a warning for health and safety issues in a site photo. We always build this in a supportive way within the work order flow, not as a standalone gimmick, but as an aid to the real work.
Which type of contractor is this suitable for?
Main contractors, smaller building companies with five to fifty employees, subcontractors in carpentry, masonry, concrete, roofing or painting, renovation and refurbishment firms, handymen businesses, restoration and heritage builders, and civil contractors with their own site teams. For sector-specific field service applications we sometimes refer to our broader field service app.
What determines the cost?
Three main factors: the number of different roles and flows in the app (the main contractor flow is more complex than the subcontractor flow), the depth of back-office integrations (one construction admin integration versus three systems together), and specific components such as BIM integration, AI photo recognition or a client portal. In the first conversation we give a realistic estimate based on your scope.