A Timex watch with a quite precise compass function, a cheap Nokia phone that compatible with most network types and a great reception, and that's it.
The less the better, it quickly gets heavy, especially once you start to need extra batteries or chargers.
>>202759Pic related would be the best when it comes to battery life, runs off 2 AA batteries, decent map, great reception, and very reliable. It's as basic as it gets, but it's enough to find your way back to civilization; won't be that good off trails though.