Thanks to apktool (http://ibotpeaches.github.io/Apktool/) I found out what was wrong.
The makefile that generates the final .apk
bundle had an error. Indeed the aapt add
command contained \
in the path instead of /
. As I'm generating on Windows, all my paths use \
as a separator. That's why I used \
for aapt add
. However as this path is used during the installation of the .apk
on Android (Unix), then I should have used /
separator.