Different Types of Power Apps

Power platform

Power platform is a low-code platform that spans Office 365, Azure, Dynamic 365 and Standalone applications.

Power Platform provides suites of services to rapidly develop and deploy business solutions.

Power App – Build no-code/low code apps within hours that easily connect to data and run on the web, iOS, and Android devices.
Power Bi – Build interactive, immersive dashboards and reports that provide actionable insights and drive business results.
Power Automate – Build Automated workflow with a no-code approach that connects to hundreds of popular apps and services.
Power Virtual Agent – Build chatbots with no code to engage conversationally with users
Power Pages (In preview) – Create customized, low-code business external-facing websites for users outside of the organization.

The entire suite of power platform services is centered around business data. This data can be external data or Internal data.

External data through Data connector with 600+ connector.
The Internal Data service that the power platform provide is known as Microsoft Data verse.

What is Power App?

Power app is a Low-code/No-code approach to Building full-featured Business applications for web or mobile users which can be easily shared.

Types of Power App.

Using Power Apps, you can create Three types of apps: Canvas apps, Model-driven apps, and Portal Apps.

Canvas App

Canvas App helps build business applications with excel and PowerPoint skill.

Starts with blank screen and design your application by adding different Controls and when UI is ready connect to Data source with Standard, Premium or custom data connector.

To create a Canvas app, we can drag and drop out-of-the-box UI control elements into canvas screens. Each screen represents a page. We can customize UI to make the app pixel-perfect.

We can create Excel-like Logic on control with Power FX formula for specific logic and connect to 600+ Data sources with Data connectors. We can Integrate the canvas app with power automates, power BI, Microsoft Teams, Office 365, Dynamic 365, and Azure.

Canvas app can be connected to both External and Internal data sources I.e. Data verse.

Different UI controls in canvas apps:

Screens
Container
Edit Forms or View Form
Gallery
Data Tables
Input fields
Buttons
Icons
custom components, etc.

Model Driven App

Start with Creating Data verse model with tables and relationships. customize the form and views in data verse. Add business rules or Business process flow to table. This Business logic will be automatically applied to model driven app views and forms.

By providing conditions and actions, we can do any of the following with business rules:

Set column values
Clear column values
Set column requirement levels
Show or hide columns
Enable or disable columns
Validate data and show error messages
Create business recommendations based on business intelligence.

The above-listed action can apply to model-driven apps. But when using Data verse for the canvas app some action that applies to the model-driven app will not apply to canvas app. This action is:

Show or hide columns
Enable or disable columns
Create business recommendations based on business intelligence.

Without data models, we can’t create model-driven app.

Advantages to model first approach in application development are:

Building a model-driven app is rapid with the help of rich component-focused no-code/low code approach.
Responsive app.

Different Components which make Model-driven apps are:

Data components: Tables, Relationships, columns, and Choices.
UI components: App, Site Map, Forms, view, custom canvas pages.
Logic components: Business rules, Business process flow, workflow, actions, power automate flow.
Visualizations Components: Charts, dashboard, and Embedded Power BI.

Portal Apps

Portals App are external-facing websites that allow external authenticated or anonymous users to access websites.

Users Outside of the organization can sign in with a wide variety of identity providers such as Azure AD, Google, Facebook or Other Provider with OpenID connect, SAML or WS-federation Protocol

Users can view and add data to the data verse table after proper authentication, table permission, and security roles are assigned to tables.

This model's first approach allows app makers to build rapid external-facing secure and scalable websites.

We can customize site pages, Layout, and content. We can reuse page designs by building templates, adding forms and views to display data from Data verse, and publish to users.

Major components of Power app Portals

List: Data verse View
Forms: Data verse Form
Advance Forms: Power portal Business process flow
Web Roles: Authenticated or Anonymous roles
Table Permissions: Read, Write, Delete, Edit, Append, Append to

Features Comparison of Canvas App, Model Driven App and Portal App.

Featured	Canvas App	Model-Driven App	Portal App
Relational data structure	Yes (if connected to Relational database)	Yes (Data verse only)	Yes (Data verse only)
Responsive	No (requires use of responsive container control)	Yes	Yes
Coding Style	Low Code	No Code	No Code
Launch Time	Medium	Low	Low
UI Control	Full Control	Limited (Custom Canvas Page)	Low (customization need)
Licensing Cost	Low (Depends on data connectors used)	Medium (Premium license need + data verse Storage if increase)	High (Additional licensing cost for Anonymous users)
Data storage capacity	Depends on Data source connected	Data verse Only (Unlimited storage with extra cost)	Data verse Only (Unlimited storage with extra cost)
External Access (Authenticated User)	Yes (guest license)	Yes (guest license)	Yes (guest license)
External Access (Anonymous User)	No	No	Yes
Security	Data source dependent	Via Data verse Security roles and table permissions	Via Data verse Security roles and table permissions
Sharing	App Shared with users	Access App using security roles in Data verse	Access App using security roles in Data verse

When to Use Canvas App.

Use canvas apps when the application needs a customized user Interface and external data source. Canvas app offer:

Graphical UI controls.
The ability to create a custom-made UI based on user requirements.
Integration with multiple data sources using connectors.
When the data source is already in place.

When to Use Model Driven App.

Model-driven apps are good for scenarios where the business logic is complex, such as:

Sophisticated data models with data verse’s tables and relationships.
Business process management like form, Views, Charts, business process flow, and business rules.
Component-focuseded approach with relationship-driven architecture.
Responsive Application.
Rapid Development is needed.