I am maintaining several nextcloud instances at fairkom, as it gives our customers back data souvereignity. In fact you host your data, calendar, addressboock by yourself (or a hosting partner you trust) and nextcloud offers nice tools for collaboration. 

The photos I create on my (Google-free) smartphone are automatically synced to a private nextcloud server in our living room. It runs on a RaspBerry Pi, which is also serving as a music and TV streaming server and to which I attached a 1 TB hard disc.