Guide to Buying a GPS Device

For geocaching, an expensive and elaborate GPS device is not necessary. At the simplest level, you will need a GPS device for which you can easily enter waypoints. A device should also be easy to use, accessible, and durable.

Geocaching Using a Mobile Phone

Although geocaching has traditionally been played with a GPS device built for outdoor use, an increasing number of mobile phone manufacturers are now supporting GPS chips. Many of these new phones can support geocaching via Geocaching Live-enabled Applications. Real-time access to Geocaching.com information allows you to go geocaching at a moment's notice.

Buying a GPS Device

You can usually find GPS units at electronic, camping and boat supply stores or online. Still cannot decide what device to buy? Ask geocachers what they use in the Groundspeak Forums. In the forums, you can search latest news, post product related questions and even browse for used devices for sale!

Device Feature Considerations for Geocaching

  • Basemap. This is highly recommended. The additional cost is marginal, and the increase in the equipment's usefulness is substantial. Driving directions to the area near a cache can be incredibly useful, so consider this feature in a higher end device.
  • Channels. Most GPS units today now have 12 parallel channels. Channels help to acquire GPS satellite signals faster and more accurately. If you are looking at older GPS devices, consider models built after 1997. Older, single-channel receivers are much slower and may not be as accurate.
  • External antenna jack. With new GPS devices this has become less important since the newer chips are sensitive enough to acquire signal inside a vehicle. However, it is not always possible to obtain good satellite coverage through a front windshield; this is when an external antenna can help. Even backpackers will benefit from the ability to safely store the receiver inside a pack with an antenna attached to backpack shoulder straps. It can also help outdoor use in places, like heavy tree cover, where signals are weak.
  • Interface jack. If you are using the receiver with a computer, be sure that it includes an interface cable so you can quickly load maps and waypoints onto your device. Newer GPS units often support USB while older devices generally have serial attachments. If you purchase an older GPS device and have a newer computer, you may need to purchase a USB to serial port adapter as well. If you own a Mac, you should check to ensure that it supports the Mac operating system.
  • Memory. This is used to load detailed topographic maps, street-level maps, or additional waypoints into the receiver. Detailed maps can use a great deal of memory on your device. Consider internal storage capacity. Higher end devices also usually accept a memory card for additional storage.
  • Power source. It is preferable to have a device that can support external power, like a cigarette lighter power cable. Due to the power requirements the device should support standard batteries (AA or AAA) for easy replacement on the trail. Lithium batteries are recommended for newer GPS models to ensure a longer battery life, and power geocachers should consider rechargeable batteries.
  • Rocker keypad or touchscreen. Using a receiver without a rocker keypad is like using a computer without a mouse. Some newer GPS units have touchscreens which helps immensely when navigating using the maps.
  • Screen size. For visual ease of operation, use a device with the largest screen that can be realistically carried. Screen size is measured diagonally. Color is great and helps define map features and a backlight is important, although both features burn additional battery power. A screen protector is important in preventing scratches out on the trail.
  • Waterproof. Sooner or later your device will get submerged. Get a device that is at least water-resistant, although an IPX7 designation is preferred. An IPX7 designation means the GPS case can withstand accidental immersion in one meter of water for up to 30 minutes. Plastic bags and boxes are also recommended for added protection.
  • Geocaching Features. An increasing number of higher end GPS devices now have functionality specifically created for geocaching that can store all the information from Pocket Queries. Some will also store drafts (field notes) to help you log your caches after a hunt.

(Excerpts from the book, The Complete Idiot's Guide to Geocaching)