I'm trying to find an official answer to my question: Can I use DelegateControl in Sharepoint 2013 on Office365?
Does anyone have any Microsoft link or article where they say this is possible or not possible? Or any of you guys know for experience this is possible?
Thansk Emilio
No it's not possible to use Delegate Control as you can only install Sandboxed solutions in SharePoint 365 and Delegate Controls are not permitted in Sandboxed solutions.
Similar question asked Office365 community
http://community.office365.com/en-us/f/154/t/55979.aspx
Richard diZerega has written a blog about what is possible and not possible on SharePoint 365
http://blogs.msdn.com/b/richard_dizeregas_blog/archive/2013/07/16/app-approaches-to-common-sharepoint-customizations.aspx
Delegate Control
Apps for SharePoint do not support "Control" elements that can be used with delegate controls in a master page. Delegate controls are a common mechanism for swapping out functionality of a site using a farm solutions (particularly useful with the AdditionalPageHead delegate). As an alternative, the same result can be achieved through the design in a custom master page (ex: place specific html or server controls in the master page).