Nothing undermines a trip like a dead laptop before a presentation or a phone that quits during navigation. A small amount of planning keeps your tools alive across a long travel day.
Carry a high-capacity battery pack and the right cables for everything you bring, plus a compact multi-port charger so one outlet serves several devices. If you travel internationally, a reliable adapter belongs in your bag permanently, not on a last-minute shopping list.
Charge opportunistically. Top up during layovers and downtime rather than waiting until a device is low. The traveler who is always a little charged is never desperately hunting for an outlet.