Usability Matters: Practical UX for Mobile Developers and other Accidental Designers.
Feedback tells us that this better fits the content and better communicates this is a book for mobile developers. Not a book for people who currently consider themselves designers or UX experts.
For today (April 25th) only it's part of Manning's Deal of the Day. Pre-order for half price with code dotd042517au at https://www.manning.com/dotd