It has been really quiet about the official Magento Mobile App so I have done a research for one of my customers that is in need of a solid, cost-efficient mobile solution that does not require building up a new site from ground (i.e. the mobile site should exist in addition to the current webpage – not replace it).
The analysis showed that the shop visitors have lots of different device screen solutions so a mobile theme / responsive design is preferred that can be used for a variety of devices.

An article from Rouven on the Webguys Blog from 2012 highlighted some modules that I want to enhance with some other extensions/themes here as well:

I will check single ones of them in separate posts regarding code quality, amount of customization work needed, usability, etc.

Personally I prefer the default Magento theme as it does not try to "emulate" the iPhone look’n’feel.

With the upcoming Magento CE version 1.8.2 in Q1 2014 the core responsive theme may also be more than interesting.