Knowing that NAP (name, address, and phone) are important search engine optimizations for local businesses that are city specific, e.g. plumbers, lawyers etc.
Is NAP still useful to a software as a service business, which doesn't have any physical address? i.e. users from anywhere can just register at the website for the product, so their physical location doesn't matter.
Citations of name, address, and phone number are very important for ranking in Google Maps searches. Google measures how "important" a local business is by counting the number of times its name, phone number, and address appear on the web.
If you don't have a physical storefront where you want to have customers show up, you don't need to worry about ranking in Google Maps. NAP citations aren't going to matter much to your website.
You will need to do the type of SEO that most websites do:
NAP falls in the category of "trust signals". There are some characteristics that legitimate web-only businesses have that illegitimate web-only businesses do not.
Legitimate web-only businesses tend to have fully fleshed-out "About Us" sections of their websites, which may include NAP. Legitimate web-only businesses have employees, and commonly link back-and-forth between the website and the social media profiles of these employees. Legitimate web-only businesses often register their domains for 5+ years, etc.
In isolation, implementing any 1 of these tactics isn't going to turn your untrusted website into a trusted one. But when you provide LOTS of these trust signals, from a variety of sources, all telling similar stories, they tend to point to web business that is doing business in good faith, and in it for the long haul.
