Is snap verified by Ubuntu SnapCraft Team similar like Apple in Appstore?
Verification about: It contains malware / spyware / virus / stealing information / unnecessary permission usage or not.
Not like Appstore.
Anybody can publish an unreviewed snap at any time, and that snap might contain malware.
It's up to you to install snaps only from trusted authors. In Deb-based Ubuntu, it's similarly up to you to choose only trustworthy software sources - Ubuntu does nothing to check PPAs and other common non-Ubuntu sources.
However:
The design of Snaps is built around preventing rogue applications from running through your system, stealing data and causing damage.
A malicious Snap package can cause you some headache...but much less than a malicious Deb package (which includes preinst/postinst scripts that run as root!)
If you discover a malicious Snap, go the the Snap Store page for that snap and report it ("Is there a problem with <name>? Report this app").
One malicious snap was indeed discovered -- in 2019, if I recall correctly. It was reported, and promptly investigated and removed. Feel free to get involved and test snaps for trustworthiness!
