Take a look at our side project Switchboard: easy A/B testing for mobile

https://github.com/KeepSafe/Switchboard It's open source

My co-founder Philipp is talking about this project at next week's Silicon Valley iOS Dev Meetup http://www.meetup.com/sviphone/events/38752252/

We just posted a comment explaining our alternative. Ping us at founders <at> leanplum <dot> com if you want to chat.

Something similar is appgrok.com which offers server-side control of bundled files, including nib files. It doesn't have a built-in experiment framework, but you could mix AppGrok with analytics to get some experiments-without-app-store-submission working, if that's your goal. (I'm a developer at AppGrok.)

swrve.com

A/B testing for mobile and social apps