The ten systems
Navigation: map and compass, plus a GPS app with offline maps downloaded. The phone is a bonus, not the plan — batteries die and screens crack.
Sun protection: sunscreen, SPF lip balm, sunglasses, a brimmed hat. Altitude and snow multiply UV exposure.
Insulation: one more layer than you think you need, always including a rain shell. Weather turns fastest exactly when you're least prepared for it.
Illumination: a headlamp — not your phone flashlight — with fresh or spare batteries.
First aid: a compact kit you've actually looked inside, plus any personal medications.
The other five
Fire: a lighter plus waterproof matches and a bit of tinder that lights when wet.
Repair kit and tools: a multi-tool and a few feet of duct tape wrapped around a trekking pole.
Nutrition: an extra day's worth of no-cook food beyond your plan.
Hydration: water plus the means to make more — a filter or purification tablets.
Emergency shelter: an ultralight bivy or even a large trash bag. In an unplanned night out, it's the difference between uncomfortable and hypothermic.
Where the phone fits (and where it doesn't)
A modern phone with offline maps and, on newer models, satellite SOS covers several categories well. But it's a single point of failure: one drop, one dead battery, one dropped signal and you've lost navigation, communication, and light at once.
Carry it, use it, and back up its critical jobs — navigation and fire and light especially — with something that doesn't need a charge.
- ✓Ten systems, not ten gadgets.
- ✓Offline GPS is a bonus over map-and-compass, not a replacement.
- ✓A real headlamp beats a phone flashlight every time.
- ✓Always pack emergency shelter, even on a day hike.