Is There a Way to Back Up Your Google Photos?

I don't like having all my pictures in a place that are just not very accessible anywhere else or on any other device other than an iPhone. I would be willing to pay, I mean I already pay $25 a month to use Google Photos. So why can't I just have that functionality? Twitter has always been a really good tool for journalism. And it's a tool that allows you to reach everyone because everyone has a Twitter.