If you have an iPhone or an iPod Plus or a mobile phone using the Symbian system then there is now an offline travel guide with a super fast loading page which provides all the usual stuff of travel guides such as: General info, Districts, Getting there, Transport, Sights, Entertainment, Shopping, Eat, Drink, Place to stay, Contact, Stay safe. Pretty much the same as most guides.
There is a slimmed down free version and the full version is a very reasonable $1.19.
Softpedia, the company behind distributing the guide, has a list showing that the publisher, Pides has already added Shanghai and Xian to its collection so it would seem only a matter of time before the whole of the major tourist destinations on China are covered.
In a separate development a Tube Map for Beijing is available at $5. This is the tube map overlaid on to a standard map so that you know where to go to catch the tube, The list available is already impressive and is being constantly added to.