Power Apps is one of Microsoft’s most powerful tools for building custom business applications quickly. But if you're managing data poorly, your app will slow down, break, or become impossible to maintain — especially as usage scales.

From choosing the right data source to understanding how to handle delegation and permissions, your architecture determines whether your app is a quick win or a long-term headache.

This blog is written for organizations just getting started with Power Platform, and who want to build their first scalable, secure application with clarity and confidence.

Choosing the Right Data Source: Your Foundation Matters

The data source you pick impacts every part of your Power Apps experience — from load times and security to scalability and supportability.

1. Excel (via OneDrive)

This is often the default choice because it's familiar and easy. But it's a trap for most business apps.

• Pros:
  • Quick to start
  • No additional licensing
  • Good for prototypes
• Cons:
  • No data integrity control
  • No row-level security
  • Terrible for multi-user collaboration
  • Performance tanks with more than a few hundred rows
• Best for:
  • Prototypes, one-time tools, solo user experiments
• Avoid for:
  • Any multi-user, secure, or long-term production app

2. SharePoint Lists

SharePoint is commonly used in Microsoft 365 organizations and is integrated directly with Power Apps.

• Pros:
  • Easy to set up
  • Permissions managed via Microsoft 365 groups
  • Integrated with Teams, Outlook, and Power Automate
• Cons:
  • Delegation limits (~2,000 items without custom workarounds)
  • No relational data
  • Hard to enforce data types and rules
  • Limited scalability with large data sets
• Best for:
  • Departmental apps, document-driven tools, internal requests
• Avoid for:
  • Complex business apps, data with heavy relationships or large record sets

3. Dataverse

Dataverse is Microsoft’s modern, cloud-native data platform — built specifically for Power Platform and Dynamics 365.

• Pros:
  • Built-in security and governance
  • Supports relational data and lookups
  • Native delegation support
  • Rich metadata and validation
  • Supports role-based access control
  • Easily integrates across Power Platform
• Cons:
  • Requires premium license
  • Slightly higher learning curve
  • Can be overkill for extremely basic apps
• Best for:
  • Enterprise-grade apps, secure apps, apps that integrate across systems
• Avoid for:
  • Small, non-critical apps with no data complexity or security needs

4. SQL Server / Azure SQL

SQL is ideal for enterprise IT teams that already use databases internally or need to manage high-volume transactional systems.

• Pros:
  • Highly scalable
  • Native relational model
  • Delegation-friendly for most functions
  • Custom views, stored procedures, indexing
• Cons:
  • Requires more configuration
  • Security setup is external to Power Apps
  • Not as tightly integrated with Power Platform features as Dataverse
• Best for:
  • Apps that require advanced queries, high performance, or custom integrations
• Avoid for:
  • Teams without internal SQL expertise or DevOps capabilities

Understanding Delegation: The #1 Power Apps Bottleneck

Delegation is the concept that determines whether a data operation is executed on the server (fast and efficient) or inside Power Apps (slow, limited).

When delegation fails, Power Apps only processes the first 500–2,000 records — even if the data source contains more. This is a silent killer of data integrity.

Why it matters:

• You may be missing critical records
• Your filters and searches won’t return full results
• Your app slows down or crashes for users

What causes delegation issues?

• Using non-delegable functions (e.g., SortByColumns, ForAll, CountRows)
• Using unsupported queries on SharePoint or Excel
• Using complex filters not supported by the data connector

How to avoid it:

• Choose a delegable data source (Dataverse or SQL preferred)
• Stay within delegable functions (Filter, LookUp, Search)
• Split logic across multiple screens or batches if needed

At HarjTech, we help clients refactor their apps to make sure delegation is respected from day one — reducing tech debt and improving speed and reliability.

Collections, Filters, and Displaying Data

Power Apps gives you multiple ways to store, manipulate, and display data — but each approach has its own use case.

Collections

Collections are temporary, in-app data tables. Use them to:

• Stage data for offline or preview
• Work with a subset of data before saving
• Store user selections during a session

But never use them as your primary database. They vanish when the session ends.

Filters and Conditions

You’ll often want to show different data to different users. Use Filter(), If(), and Switch() functions to dynamically show or hide records based on context.

Examples:

• Show only “Active” projects
• Display approvals for the logged-in user
• Limit access to sensitive records

This logic makes your app feel tailored — and enforces basic business rules through the interface.

Galleries

Galleries are how most data is displayed in Power Apps — from cards to lists to custom dashboards.

They can be tied to collections, SQL, Dataverse, or SharePoint — and support full customization. Best practices:

• Limit the number of visible items
• Avoid nested galleries if possible
• Use conditional formatting for clarity
• Enable drill-down navigation

Managing Permissions

Data security isn’t just about access — it’s about control.

At the Data Source:

• SharePoint: Use lists with Microsoft 365 group permissions
• Dataverse: Use role-based access control and row-level security
• SQL: Use database roles, views, and stored procedures

At the App Level:

Use logic like If(User().Email = ...) or Azure AD groups to:

• Hide admin features from regular users
• Route users to different screens
• Control who can submit or edit forms

HarjTech builds all apps with layered permission models to protect data without getting in the way of usability.

How HarjTech Helps You Do It Right

Most teams can build a Power App. But building one that’s secure, scalable, and supports your real-world workflows? That takes experience.

HarjTech has helped organizations across Canada — from public sector teams to private enterprises — modernize legacy systems using Power Apps, SharePoint, Power Automate, and Azure.

We help you:

• Architect the right data source strategy
• Build apps that won’t break at scale
• Solve delegation and performance challenges
• Set up governance, environments, and ALM
• Train your team to own and evolve the platform

Need to Build a Smart App with Power Platform?

If you’re just starting with Power Apps and feel overwhelmed by data choices, performance issues, or governance — let’s talk. We can help you build smarter from day one, or clean up a project that’s already live.