All the apps make it very difficult to create a post. You have to know what community you will be posting to, search for the community, click the three dots, click create post, click whether it’s a photo/link/text and then start posting.
Why not just have a Create Post button with the title field, url field, body text field, and a button to upload a photo and then a choose community button
Eternity has a big plus icon in the bottom right corner, doesn't get much simpler than that