Below is a brief list of what Entacore Systems can offer you:

GPS We have experience in integrating GPS chips on to custom PCBs. We can also solder small LGA chips for small production runs.
RF We can develop custom RF modules from the ground up as well as interface with existing RF modules. We can also provide or write complete RF protocol code for your needs.
Software We specialise in desktop software using pure Win32 or the Qt SDK.
Internet We can develop anything from web apps to content management systems
Graphics We have experts on help specialising in OpenGL. We can provide you with realisic real time renedering.