Sergio Viudes Carbonell is a 32-year-old developer from Elche (Spain). He has loved to play video games since his childhood days (since the ZX Spectrum was around). Also, he has drawn and composed electronic music as a hobby. Then, he started coding and studied computer engineering at the University of Alicante.

He started working as a software and web developer. But he always wanted to create video games. So, he founded Baviux and now Sergio, designing and developing mobile apps and games. He has reviewed the following books for Packt Publishing in the past:

Antonio Hernández Niñirola is a European PhD candidate in software engineering in the last phase of his doctorate program. He has a BSc in computer science and a masters degree by the University of Murcia in Spain.

Currently located in San Francisco since May 2015, he is working as part of the Android development team at Yelp.

In the academic year 2013-14, he worked with the Department of Software Engineering in the Université Mohammed V in Rabat. This was a great opportunity to focus on his research on mobile usability and resulted in several academic papers for both JCR journals and CORE conferences.

He has also collaborated with Packt Publishing in the past as both author and reviewer. If you want to learn more advanced techniques on testing and security for Android, check out his book Testing and Securing Android Studio Applications, also published by Packt Publishing. If you are new to Android development, you can check these books he has reviewed: Android Studio Application Development and Android Studio Essentials.

For more information on him, visit his website (http://www.ninirola.es) and follow him on Twitter at @hdezninirola.