Building Custom Web Apps Using PowerApps

Building Custom Web Apps with Microsoft Power Apps

What Makes Power Apps a Web App Platform

Power Apps is not just a mobile-first tool. Canvas apps run in any modern web browser. Power Pages creates full external-facing websites. Both deployment patterns use the same connector ecosystem and the same Power Fx logic language.

The advantage over traditional web development: you connect to enterprise data sources (SharePoint, Dataverse, SQL, Dynamics 365, Salesforce) through pre-built connectors instead of writing custom API integrations. What takes a developer weeks to build from scratch takes hours or days in Power Apps.

Four Web Deployment Patterns

1. Canvas Apps in a Browser

Canvas apps run directly in any modern browser at their published URL. Users don't install anything. The app behaves like a web application — responsive layout, form logic, data reads and writes — with the same capability as a canvas app on a mobile device.

Best for: Internal web tools that don't need SharePoint or Teams integration — data entry forms, approval dashboards, internal lookup tools, reporting screens.

• Runs at make.powerapps.com or a custom published URL
• Responsive design for desktop and tablet browsers
• Power Automate integration for workflow logic triggered from the app
• Azure AD authentication — users sign in with their Microsoft 365 credentials

2. Canvas Apps Embedded in SharePoint

Canvas apps embed into SharePoint modern pages using the Power Apps web part. The app appears as a native part of the SharePoint page — users don't navigate away to use it. The app reads from SharePoint lists, Dataverse, SQL, or any connected data source.

Best for: Department pages that need interactive functionality — team request forms, quick data entry tools, interactive lookup widgets — without leaving the SharePoint intranet.

• Add the Power Apps web part to any SharePoint modern page
• App inherits SharePoint page navigation and branding
• Can read from and write to the host SharePoint site's lists and libraries
• Passes SharePoint context (current user, current site) to the app automatically

3. Canvas Apps as Microsoft Teams Tabs

Canvas apps become Teams tabs — pinned to a channel, a chat, or a personal workspace. The app surfaces inside Teams without users switching to a browser. This is the most adopted web deployment pattern for internal-facing Power Apps.

Best for: Team-specific tools that belong in the collaboration context — project status boards, team resource tracking, meeting preparation forms, incident reporting.

• Add as a tab in any Teams channel, group chat, or personal workspace
• Teams context (current user, team, channel) passed to the app
• Notifications and approvals trigger Power Automate flows that surface in Teams
• No additional licensing beyond standard Power Apps per-app or per-user license

4. Power Pages (External Web Portals)

Power Pages (formerly Power Apps Portals) creates fully external-facing websites. External users — customers, partners, vendors, applicants — authenticate and interact with your data without a Microsoft 365 license.

Best for: Customer self-service, partner portals, grant or application intake, vendor management, and any process that currently runs through email with attached forms.

• External authentication: Azure AD B2C, Google, LinkedIn, or local account registration
• Responsive design — works on mobile, tablet, and desktop
• Role-based access — different external users see different data and pages
• Data writes directly to Dataverse — no manual import from a form inbox
• Embed Power BI reports for external data sharing on the portal
• Custom domain support — the portal runs at your own domain, not a Microsoft URL

Power Pages vs Canvas App in Browser

What Power Apps Web Apps Connect To

All four web deployment patterns share the same connector ecosystem:

• Microsoft data: Dataverse, SharePoint, Azure SQL, SQL Server, Excel Online, OneDrive, Teams
• CRM/ERP: Dynamics 365, Salesforce, SAP, ServiceNow
• Databases: Oracle, MySQL, PostgreSQL, Azure Cosmos DB
• External APIs: Any REST API via custom connectors
• Productivity tools: Outlook, Google Workspace, DocuSign, Box, Dropbox

EPC Group Web App Services

EPC Group builds custom web applications on Power Apps for enterprise organizations. Our web app practice covers all four deployment patterns:

• Requirements analysis and deployment pattern recommendation before any build begins
• Canvas app development for browser, SharePoint embed, and Teams tab deployment
• Power Pages external portal development with Azure AD B2C authentication
• Custom connector development for internal line-of-business APIs
• Power Automate workflow integration for form submissions, approvals, and notifications
• Power Platform governance — DLP policies, environment strategy, maker policy
• Migration of legacy web forms (InfoPath, SharePoint Designer, HTML forms) to Power Apps

Frequently Asked Questions

Can Power Apps web apps run on a custom domain?

Power Pages portals support custom domains with SSL. Canvas apps run on Microsoft-hosted URLs by default. For organizations that need an internal Canvas app at a custom URL, embedding in SharePoint or deploying as a Teams tab is the recommended approach.

What is the difference between Power Pages and Power Apps Portals?

Power Pages is the renamed and redesigned version of Power Apps Portals. The capability is the same — external-facing web portals connected to Dataverse. Power Pages has a redesigned studio interface and additional low-code design tools compared to the original Portals experience.

Can external users submit forms without a Microsoft 365 license?

Yes, through Power Pages. External users authenticate with Azure AD B2C, Google, LinkedIn, or a local account — no Microsoft 365 license required. Each authenticated external session is billed per-login or through a Power Pages Authenticated User licensing model.

How long does a Power Pages portal project take?

A focused Power Pages portal with one user role, a single form, and Dataverse integration typically runs 4–6 weeks. Multi-role portals with Power BI embeds, custom authentication, and complex data relationships run 8–16 weeks.

Start Building Your Custom Web App

EPC Group builds Power Apps web applications for enterprise organizations — from focused departmental tools to multi-role external portals. Fixed-scope engagements with requirements documentation before any build begins.

Call (888) 381-9725 or contact us online to discuss your Power Apps web project. You can also book directly with our Power Platform practice.