Books

Most comprehensive positions:

ISTQB Foundation Level Mobile Application Testing

https://www.istqb.org/certification-path-root/mobile-application-testing.html
Hands-On Mobile App Testing (2nd edition) | Daniel Knott

https://leanpub.com/Mobileapptesting
Mobile Testing by Rex Black

https://www.amazon.com/Mobile-Testing-Rex-Black/dp/1780174047

More:

"Smartwatch App Testing" | Daniel Knott

https://leanpub.com/smartwatchapptesting
ASTQB Mobile Tester

https://www.astqb.org/documents/Mobile-Syllabus-ASTQB.pdf
"Tap Into Mobile Application Testing" | Jonathan Kohl

https://leanpub.com/testmobileapps
"Tap Into Mobile Application Design" | Jonathan Kohl

https://leanpub.com/mobileappdesign
"App Quality: Secrets for Agile App Teams" | Jason Arbon

https://www.amazon.com/App-Quality-Secrets-Agile-Teams-ebook/dp/B00JVAR7EM
"Software Testing: A Guide to Testing Mobile Apps, Websites, and Games" | Mark Garzone

https://www.amazon.com/Software-Testing-Guide-Mobile-Websites-ebook/dp/B00O76JWMU
"Beginner’s Guide for Mobile Applications Testing" | Jeesmon Jacob

https://www.amazon.com/Beginners-Guide-Mobile-Applications-Testing-ebook/dp/B00TD42HIM
"Software Test Attacks to Break Mobile and Embedded Devices" | Jon Duncan Hagar

https://www.amazon.com/Software-Embedded-Innovations-Engineering-Development/dp/1466575301
"Android Apps Security" | Sheran Gunasekera

http://www.apress.com/9781430240624
"Mobile Application Penetration Testing" | Vijay Kumar Velu

https://www.packtpub.com/application-development/mobile-application-penetration-testing
"Application Security for the Android Platform. Processes, Permissions, and Other Safeguards" | Jeff Six

http://helion.pl/ksiazki/application-security-for-the-android-platform-processes-permissions-and-other-safeguards-jeff-six,e_2gec.htm

Partially about mobile testing:

"Learning Pentesting for Android Devices"

https://www.packtpub.com/hardware-and-creative/learning-pentesting-android-devices
"Android Hacker's Handbook" | Joshua J. Drake, Zach Lanier, Collin Mulliner, Pau Oliva Fora, Stephen A. Ridley, Georg Wicherski

http://eu.wiley.com/WileyCDA/WileyTitle/productCd-111860864X.html