You can post your privacy policy on the app or, better, reference a website with your privacy policy. (You can create a website through Google Sites for free.) In the metadata for your app there is a place to insert your website for the privacy policy.
Here is an example of a privacy policy:
XYZ Software does not collect any personal information from any of your use of our Apps. If we have any of your personal information we will not willingly sell or give it to anyone, except if lawfully subpoenaed to produce it and then only after offering you a reasonable chance to challenge such subpoena if allowed by law.
And a kids app has to have a 'parental gate' in it before a user can get out of the app (e.g. to facebook)