Options for server side rendering the ang apps
1 - pretender.io Free for up to 250 pages per month Here is a tut.: https://scotch.io/tutorials/angularjs-seo-with-prerender-io
2 - https://github.com/steeve/angular-seo Open source and free
_escaped_fragment_ idea ie:
localhost/app.html#!/route becomes:
localhost/app.html?_escaped_fragment_=/route
At the server side, phatomjs picks up this translated request and returns a full rendered html file for google to crawl.
However has anyone tried running a plain ang app with a site map? I am building an api onto Kirby CMS which has a nice site map functionality... but I don't know if this will be enough for seo...
It depends. Google will try to crawl ajax calls
https://developers.google.com/webmasters/ajax-crawling/docs/learn-more
However this can't be said about other search engines or crawlers.
Sitemap will not help you much, because it does not contain all content of your site. Sitemap is basicaly there to give crawlers map what they should crawl/index.