GPS or Compass Pros and Cons

Characteristics	Compass	GPS
Cost	Low	High
Dependability	Compasses can give false readings, but these can usually be avoided with care. Keep the compass away from all metal objects since these can deflect the magnetic needle. Many geological formations and rocks are magnetized and can affect compass readings, as can electricity power lines and cables.	A GPS requires a strong signal to work accurately. It won't receive a signal inside most buildings or in caves and sometimes under heavy forest cover or even just a cloudy day. Batteries can run out. By controlling the only fully operational satellite navigation system in existence today, the United States could disable GPS navigation signals in times of conflict.
Display	A compass must be used with a large paper map, which helps give an area a broad geographical context.	GPS displays are too small to give you a good sense of geographic context.
Ease of use	Using a map and compass requires a higher level of navigational skill and understanding.	An electronic device that demands a lower level of navigational understanding, although extensive (and expensive) training is required to use to its full advantage. Easier to use than a traditional map and compass when walking.
Range of functions	Without a map, a compass only shows you north.	Can store a range of maps and can pinpoint exactly where you are on a map. It will let you know how much distance you've covered and how much further you have to go. It can also estimate your altitude.
Risk of breakage	Simple and robust technology with a very low risk of breakage.	It can break or stop working if you drop it or if it gets wet.
Weight	Lightweight	Heavier and more bulky. Spare batteries must be carried.

Conclusion
A GPS unit provides far more detailed navigational information than a compass, although the navigational understanding required is more superficial. Using a compass with a map gives a broader geographical context, helps you remember the route and learn about other things on the way. A compass and map are more reliable but require a higher level of navigational skill and understanding and should always be carried on a trek.