I didn't try Netfliy CMS yet, even though I use Netlify very much.
You should try it... The best part is that you can set up the structure of your data just within a single .yml configuration file. Also, you access it from your own domain. /admin. Also, it works well with most static site generators.
The content is saved in your own repository. (you can use Github, Gitlab or Bitbucket).
Forestry.io also saves data to your repository, so in most projects, I use both forestry.io and netlify cms. I love forestry.io because it's mobile editor is awesome!
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