There's an interesting article on Gizmodo (so please take it with a grain of salt) about trying to cut Google out of your life - long story short, it's surprisingly hard and some things you wouldn't expect will break.
YMMV. I mostly moved off Google for my own usage last year and deleted my paid Google Apps account (let’s ignore work usage as that’s out of my hands). Remaining services I use are YouTube (no competitor), books.google.com (occasionally, when Hathi is proving too slow) and groups.google.com (the project I mostly contribute to organises there). Of those three I could dump books.google.com without too much effort and I only interface with groups.google.com via email; moving to another provider would be totally possible if needed.
True enough. I found the things mentioned in the article interesting because you also lose things like Google Web Fonts and a number of services which depend on the Google Maps APIs for mapping.
Unfortunately, I won't be able to completely disconnect because I've got a number of friends who share photos through Google Photos (and I would like to keep access to those), a number of friends who only use Hangouts (not sure if that's better or worse than FB Messenger), and YouTube doesn't have any real competitors.
https://gizmodo.com/i-cut-google-out-of-my-life-it-screwed-u...