I designed a connected breast pump and prototyped its app component in Marvel. I made all visual assets in Sketch in one day.

I first articulated the user's main tasks. Zoe (our user persona) needs to...
1. control her pump.
2. understand her stockpile of milk.
3. share her stockpile information with other caretakers.

Then I sketched how Zoe might complete the three tasks:

I wanted the app to be bright, so I tested a few color schemes.

I made two iterations of a "looks-like" prototype for user testing. Here are the main three screens: