K9Mail with Fastmail, AddressToGPS + OSMAnd, I back up my own photos with a home server and some rsync (Syncopoli). There is PhotoBackup which is kind of neat though.

We use Google Calendar for stuff at work, Google still has an old psuedo-deprecated-not-talked-about CalDav endpoint I hit with DavDroid that gives me all of that. These problems were solved with protocols long before gardens. I use offlineCalendar(Yes you need an app for that in Android) to create a calendar for myself locally, though I have a radiCAL server for things I need sync'd. Could have used Fastmail I guess.