@indigo Depends a bit on what the content in question is. All my writing lives in Simplenote on mobile, and Notational Velocity (the original, not Alt) syncs to it on the Mac. Have used the web interface in a pinch, although I don't fancy it as much.
My cookbook get exported out of Evernote when they started sucking too much and it lives in Apple's Notes right now, although that's just a big unsearchable mess that I need to deal with some time.
Videos I have Air Video for, but only at home on my own network, not over the scary net. Should probably look into alternatives here, but I'm lazy since it works as well as it does.
Photos live in Apple's Photos app on respective platform, but I need to get my albums in order and put things where they are supposed to be for future reference ans such. Syncs reasonably well, but some teeth grinding occurs every so often.