Power Apps is a suite of apps, services, and connectors, as well as a data platform, that provides a rapid development environment to build custom apps for your business needs. Using Power Apps, you can quickly build custom business apps that connect to your data stored either in the underlying data platform or in various online and on-premises data sources (such as SharePoint, Microsoft 365, Dynamics 365, SQL Server, and so on).
Because SharePoint Framework makes use of a widely known web development stack, spfx solutions may be created on any platform, including OS X and Linux, using any code editor of your choosing. In this Microsoft powered SharePoint development model, it does not employ a proprietary model but rather tools and techniques that are widely utilized by developers across all platforms and stacks. In addition, the Product Group is dedicated to building their solutions on top of the framework using only publicly available APIs, which will support developers.
Power Apps vs Sharepoint Framework
Even for small applications, the load time taken by Power Apps is more.
Performance is better than Power Apps. Small or large-scale applications load quickly compared to Power Apps.
Multiple out-of-the-box connectors are available for connecting with a variety of data sources which makes the process easy.
Data Connections require a bit more setup to be done in SPFx, but they can be tailored to do exactly what you want.
Time to Build
Power Apps takes less time to build apps/forms than SPFx as it's a low code solution.
SPFx takes more time to build the apps/forms/solutions as more development efforts are required.
Size of Application and Customization
Suitable for small-scale applications. Even though there are options available for customizations, you will not have complete control over them.
Suitable for small & large-scale applications, it can be fully customized. But for small applications, development efforts & time required can outweigh the benefits.
Excel background (Excel formula structure & cell construction is closely related to Power Apps), Math, logic, design.
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