The keystores generated by the new build system generate signatures using a SHA256 algorithm, which does not work with some older Android devices (mostly pre Android 4.3). This means that builds made with the new cert management system currently create APK files that may not install on some Android 4.0-4.2 devices (some devices will install, some will fail, depends on the manufacturer).
The second algorithm is currently being applied, whereas, the first should be applied for maximum compatibility. The issue is currently being worked on and will be addressed as soon as possible. In the meantime, there are two workarounds:
jarsigner -verbose -sigalg SHA1withRSA -digestalg SHA1 ...
Correcting this issue requires updates to our build system and will not require an update to the Intel XDK client app (the application that is installed on your development system).
Andre -- the problem is being worked on in the build system. It should be resolved early next week. Testing on fixes has already begun. If you need to publish something immediately, it would be best to do a self-sign. See this FAQ for pointers on how to do that > https://software.intel.com/en-us/xdk/faqs/cordova#manually-sign-android-apk
The fix is live. Please try it and confirm that it fixes your issue.
Sometimes issues look the same (shoe the same symptoms) but require different fixes, so we can only test against the issues we've been able to reproduce. If it turns out that your issue is not fixed, we need to know so we can identify the root cause of that issue and correct it.