A basic mockup of a sign-up/sign in screens along with a 2-way authentication of a uniquely generated code each time.

Basic To Do prototype based on: https://www.sketchappsources.com/free-source/3625-basic-to-do-app-design-sketch-freebie-resource.html

A simple spaceship animation using 'Animate Item' & states. Design Source: https://www.sketchappsources.com/free-source/3673-rocket-illustration-sketch-freebie-resource.html

JF