We already knew Yellow since we have already completed a web development project together, so we decided to choose them to embark on the design project for an iOS app. We needed some illustrations for onboarding, a simple UI/UX design for main screens, and the logo redesign.First, they created several illustrations in three styles, then via A/B testing we chose the final version and finished the rest of the project in that style. Since we worked together before, it was easy for us to coordinate the processes and find a common ground.