Reasons Not to Use Google (2015)
This is an interesting list of reasons.  Even if it is long, I'd say it's still somewhat incomplete...I was motivated by this list to stop depending so much on google.  But it's harder than it seems.  For example, if you purchase a fastmail account, you still need a google account to install the app in your non-google phone, because fastmail only provides the apk files via the google play store.  There's so many such "roadblocks" in de-googlification that you inevitably give up at some point.