Well, if you're willing to buy RubyMotion:

http://www.rubymotion.com/

I made an iOS app using vim and Lua (via wax - https://github.com/alibaba/wax). Obviously needed the xcode toolchain for compilation and libraries but always from the CLI / scripts.

Getting the code building with M-x compile should be fairly straightforward.

For deployment + debugging, you could try this: https://github.com/phonegap/ios-deploy

Looks like it runs lldb itself, but perhaps with a bit of work you could get it to interact with gud-mode?