I used to work with SP2010 and with external users. Most of my applications the users just login in the site collection and submit data as long as perssion allowed them. I want the same scenario in SharePoint Online however SharePoint Online doesn't have public site collection.
Ok, I can add users as external users. I know that I can share the site collection with them, but which would better....create an AD account for theis external users and sync those with Office 365 or just use as external users by sharing lists and site collections?