This is a topic discussed here numerous times in the past.
See I need help with what should be an app and what shouldn't - #2 by KenWhitesell to get started. (There are links to links to links, etc - there’s a lot to read here about this.)
Our basic position is “One app until it hurts, then think about creating multiple apps.” What this really means is that we don’t preemptively start the design of a system around multiple apps. The decision to create those apps have to come from the design, not by driving the design in that direction.