Portable GPS units come in many flavors, including stand-alone devices and GPS built into a PDA or a cell phone. Portable GPS satellite simulators can fit in the trunk of a car, and are often used for testing. They are available as commercial off the shelf products. Portable GPS units are also used widely for regular civilian activities like navigating your car through traffic, for finding road directions in a new area, for finding your route when hiking, biking or walking. You can also use a GPS tracking system to keep an eye on your children or your pets.

Garmin offers a wide selection of handheld portable GPS devices such as its Rino 530, which doubles as a two-way radio with a range of 14 miles. Garmin Mobile 20 also has powerful short message service (SMS) integration that lets users send their position or information to any other phone via text messaging. In addition, Garmin Mobile 20 has application programming interface (API) features that support customized third party location based services (LBS) or enterprise applications.

TomTom’s portable GO 910 heads the company’s GO series, and sports a 4-inch widescreen touchscreen, Bluetooth, MP3 playback off of the 20GB hard drive, and extensive iPod integration. Sounds like most of the features function well and as advertised. TomTom also integrated in the Go 720 a FM Transmitter, which will allow you to play mp3s saved on the SD Card of the GPS on your cars radio.

Consumers should note that premium features such as real time traffic reporting may require either a subscription fee, optional equipment such as a traffic receiver, or both. Consumers should note that premium features such as real time traffic reporting may require either a subscription fee, optional equipment such as a traffic receiver, or both.