is the sellfy app a scam

Hi Recx212

welcome to the Apple (user-to-user) Community.

Re: is the sellfy app a scam : Is the e-commerce app Sellfy a legitimate app or is it a fraudulent app?

Sorry we have no way of knowing for sure, unless someone who has experience with that particular app replies.

You are suspicious enough to ask, so the app's value may be questionable.

Apple support's online article:

Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support

says:

"If you're prompted to download software"

Use extreme caution if you download content from the Internet. Some downloads found on the Internet may not contain the software they claim to, or may contain software that you didn't expect or want. This includes apps that ask to install configuration profiles that can then control your device. If installed, unknown or unwanted software may become intrusive and annoying and could even damage your Mac and steal your data. 

To avoid unwanted, fake or malicious software, install software from the App Store or get it directly from the developer's website.

Find out how to safely open software on your Mac or remove unwanted configuration profiles from your iPhone, iPad or iPod touch.

All the best :-)

Thank you kindly, Recx212, for letting us know you found us helpful. Cheers :-)