ThingMaker lets you create and store a collection of items, devices, or equipment using the design sequence found in the Traveller5™ roleplaying game Core Rules.
Each Thing can have multiple variants (TL differences for example) and each variant can have a protective case added. There's a text export option for your completed designs.
The images in the App Store show equipment I adapted from the World Builder's Handbook.
App Store Link:
https://apps.apple.com/us/app/id1532129744