What to consider when looking for a Marine GPS:

Quick list

1. Screen Size

2. Color or Monochrome

The sun's reflection can make the monochrome tougher to see

3. Mounting Needs

4. Combo -- Do you want a device that also includes a fishfinder

5. Mapping software - What does it include

Number of Channels	12 channels is fairly common
Accuracy Abilities	WAAS ready, EGNOS
Case Design	Rugged
Backlit Keypad	Nice for night fishing
Tracklog Amount	Records number of trips you can store
Waterproof	Suitable for water based activities - Seems obvious, but check
Storage Media	Brand specific or does it take a “Standard” data card
Internal or External antenna	Do you have a preference
Special Features	MOB ( man over board) number of wavepoints
Serial Interface ability	Do you plan to additional programs, maps and trip storage
Various price points
Warranty length