Am I right in my understanding that if I use on-premise app part hosting with Office 365 that I'll have to have an on-premise SharePoint 2012 site? I was hoping I could host on any IIS site, I don't need on-premises SharePoint for anything but my app part
hosting - but my reading suggests that just for the authentication to work I'll need it.
If that is so - how much is it going to cost me, or rather what licenses do I need for my on-premises SharePoint? If I have say 250 users in the Office 365 site do I need to have my SharePoint 2012 site licensed for all 250 users or do I just need a external connector? I'm thinking Azure could be substantially cheaper because of this licensing alone excluding all my other hosting costs. My Office 365 would not be using ADFS in this project plan. Can you provide any insight or advice?