Newstap is your only choice when it comes to accessing Usenet from iOS. So the author has gotten away with creating a mediocre news client. Competition in this area would be great, as it would force the author to listen to the many good suggestions given to him regarding ways to make the app better. He seems to be unwilling to invest much effort into it other than periodic bug fixes and very small features.
Some common gripes about Newstap that the author has so far ignored:
Newstap is very slow, and really doesnt have to be. Compared with news clients on Mac OS and Windows, its dog slow, which is the opposite of what you want on a mobile device where time matters. A mobile Usenet client should be at least as fast as desktop clients - if not faster! Newstaps network code needs to be greatly improved.
Newstap doesnt mark cross posted articles read in all other groups when you read them. So you end up marking them read again and again. Any decent news client should do this for you automatically!
Newstap doesnt support shared newsrc files hosted on an FTP or WebDAV server, which means if you read news with any other news clients, you get to play the laborious "use a computer to sync the newsrc from here, sync it over there when you are done, update it over there with another client, sync it back over here again, blah blah blah" game, which goes against the idea of mobile computing and makes using this app much more painful than it should be!
Newstap has an annoying bug where sometimes while you are authoring a reply message, the keyboard will obscure the bottom portion of the message, preventing you from seeing or editing anything behind the keyboard. This bug has been around for a long time - multiple versions.
I could go on, but the point is Newstap is a workable Usenet client, but not a good one. It needs significant improvement to be worth the $4 the author is charging.