Do SharePoint Add-ins overlap SharePoint Framework solutions in any way?

Question

I've explored SharePoint Framework solutions and I'm familiar with SharePoint add-ins. It's not clear to me the exact relationship between the two. Is it an either/or scenario or more of a mix?

Can a SharePoint Framework solution be delivered as an add-in? Can an add-in and a framework solution interact with each other? Would that be useful or necessary if it were true? I'm not sure where the two patterns overlap or intersect.

Answer 1

Addin:

1. App part loads in an iframe.
2. Every authentication requires a request to be made from host web to app web.
3. Impersonation possible.

Spfx web part:

1. These are web-parts with real web part properties(configurable). Directly sits in the DOM (Data object model). If coding standard is in accordance to Microsoft, web part will be working the same with all future updates.
2. Authenticates in the traditional API's format. Quicker than Addins. Less latency for clients. Smoother experience.
3. Impersonation not possible. A client-side code will do what the user is capable to do in SharePoint. Although I am visualizing of achieving impersonation using external REST endpoints. These could be called from within the client side web parts.

You may start with SPFX here: Spfx

For me spfx is the way to future. Hope that helps!