Here is another example of SharePoint All In. A new article title “SharePoint Online: An Overview for Developers” has just been released on MSDN. I often get asked about how to develop solutions for SharePoint Online. This article covers all of the information you need to get started developing SharePoint Online solutions.
There are 2 questions that get asked every time I present this topic. The article has a couple of nice diagrams that explain this well.
In the Developing SharePoint Online Solutions section there is a diagram that describes how to develop and deploy solutions to SharePoint Online. The process is generally the same Online as it is On-Prem. You design/develop the solutions on a local developer build of SharePoint and then you give your administrator the completed SharePoint package file (*.wsp) to deploy to the Sandboxed Solution Gallery.