I have been using Google Apps for Education to create and save the documents that I need for my everyday teaching. I create assessments, keep records, and even upload student work to Google apps. In later years students will create and share work with their teachers within this platform as well. I will even get to that point with my first graders later in the school year. What is nice about this as a means for a digital portfolio is that this account stays with them from Kindergarten through graduation.
I have been an avid user of Google Forms and Google Sheets in particular for the last two years. At the request of a colleague, I chose to present the tips and uses I've learned with my district colleagues at the Hilliard City Schools professional development day, Hilliard University. You can view my presentation below.
I am by no means an expert at using these tools, but there are a few things that I have learned and used that makes keeping up with all of my data and documents much more manageable. Feel free to let me know if you have any questions. I will try my best to answer what I can.