Packing List Checklist, developed by Mariano Rezk, is a free iPhone app that helps users prepare for their travels. With its Pick Suggested Items feature, users can easily select items from categories such as Essentials, Accessories, Baby, Beach, and many more, without the need for typing. The app also allows users to sync their travel lists across all their iOS devices via iCloud. Moreover, users can set reminders and manage item quantities to ensure they don't forget anything important.

With Packing List Checklist, users can create their own categories and reuse existing lists to make packing for their travels more efficient. The app also features two sections, To-Do and To Pack, to help users distinguish the actions they need to take before and during their travels from the things they need to pack.

Overall, Packing List Checklist is a must-have travel companion for anyone who wants to make their travels stress-free and enjoyable.