I am building a web application using nodejs and angularjs.
For each page in the application, I have a .js file containing an angular app for that page.
Currently, I have a total of 17 Apps for 17 pages.
I want to know if there’s any downside to doing this, as opposed to having one large app, and creating controllers for each of the pages?
Worrying about this before you have your app finished is premature optimization.
Angular.js do have support for several applicationson the same page, I believe that it is highly unlikely that they would supposed this if it was devastating for the performance.
EDIT: I obviously misunderstood your question about the several applications.
I do not think that there is any technical downside to split the application as you do, but again, you can always refactor this at a later stage if it happens to be a problem.
Get your site up first, worry about technicalities like this later!