If the vendor's app isn't available for their streaming device (or is barely usable - I'm looking at you Amazon), they can use Vudu, or Amazon's, or Google's, or whatever.

Source: https://news.slashdot.org/story/23/02/23/2336200/why-the-disc-format-has-yet-to-die-for-some-tv-series?utm_source=rss1.0mainlinkanon&utm_medium=feed

It is also helpful to know that she stocks a huge number of credits, so players can sell a vast amount of valuable weapons to her without worrying about draining all the vendor's credits.

Source: https://gamerant.com/starfield-new-atlantis-best-activities/