Papago! is a GPS navigation app for the iPhone and iPad that covers many areas in Southeast Asia including Vietnam, Hong Kong, Taiwan, and in this case, Singapore + Malaysia. There are different versions of the Papago! Singapore + Malaysia guides available at different prices on iTunes. There is an older Lite version for $14.99 and a Pro version for $24.99 for the iPhone, and a special HD version for the iPad at $29.99.
Graphically, Papago! Singapore + Malaysia is a delight. The maps are clear, instructions are simple and readable, and the interface is both intuitive and easy to work while driving. There's a search function to help you navigate, as well as several special modes for visualizing the route. The maps can be switched between 2D and 3D, and both landscape and portrait modes are supported. There's a landmarks display option, as well as road elevation mode. In the case of Singapore and Malaysia, there are images available, too.
This type of app will be useful for those living in Singapore and Malaysia, of course, but it can be even more useful for travelers. We've used the Vietnam maps to navigate around Ho Chi Minh City and Hanoi by motorcycle in the past, and the interface used by Papago! has always been excellent. If you're visiting any of the destinations supported by Papago! you will find these apps superb.