@vincent @maique SmugMug is more about making your own photo website and selling your stuff, whilst Flickr is mostly used for the social side of things. At least from the broader, public perception.

Then you can look at possibly VSCO or 500px. I think there are others but these four are the most prominent Instagram alternatives.

I've never used SmugMug and barely used Flickr. TBH if I had the money right now I don't know what I'd do, since I'm not sure how strong the photography enthusiast communities are for each service, especially as compared to just using your own site.