My problem is that if I compile my project, it adds a 2 to the build number.
So if i have the versionCode (buildNumber) 90 it is 902 in the apk file.
Infos can be found here: http://stackoverflow.com/questions/32008127/ionic-build-number-wrong-in-config-xml-file?noredirect=1#comment52067473_32008127
I tried it on a windows pc and a mac with the same result.