Due diligence prior to adding new software, apps, tools, plugin into environments

What is the industry standard practice for due diligence prior to adding new software, tools, plugins, etc... into your environment.

Also, apps from app stores, both Microsoft and Apple. Google and Apple verified, imo, is not enough.

app apple apps app stores cybersecurity due diligence environment environments etc google imo industry microsoft plugin plugins practice software standard stores tools verified what is