Application consists of three pages in team site. Admins should just be able to edit and publish the pages (both design and approve).
- Do they need to be Site Owners or just Approvers.
- Is it possible to give permissions at individual page level so some admins can edit only a particular page.
If you use native SharePoint group, you need to be in a group which provide "Contribute" right and a group which provide "Approval" right. So your user need to be part of members group and approuvers group.
In order to edit a page, you don't need to be Site Owners, members is enough.
Yes you can assign right on an individual pages. You have to break the inheritance (to delete the default mask) on the page and then assign new right to this page.