Bither for iOS.
Thanks for suggesting Bither but it is from my view not looking user-friendly and you need to many steps
I don't get you. Have you tried it? I think it's very easy.
Download, install, open, click "+" button, choose number of address to create and click 'Generate'. Maybe you should give it a try. BTW, I don't suggest using HDM before familiarizing with Bitcoin wallets.
P.S. You can also give breadWallet a try. It is simple and easy .
Did you try Hive? It seems easy to use. They use a kind of addressbook with peoples faces and simply press on the face to send bitcoin.
Hive iOS isn't decentralized AFAIK. Don't know if code is changed though.