Just to close this "incident", and let it be constructive for future unexperienced people, the option "Developer" is not commonly present among the Settings of Android devices. For this reason, the explanations given in "Beginners Guide" need a prerequisite. Otherwise you need to go on Internet and find the reason why the "Developer" (or something else related to local Lanquage ) doesn't appear in the Settings. As a matter of fact, in two tablets, I didn't have the Developer option and was frustrated. If you commonly use B4A-Bridge, commonly you don't need it. To make the Developer options to appear, it is necessary to go on the Device specifications (normally last item in Settings), where Android compilation data are present, and tap on the number of compilation for some times. At each time it will appear a message showing a decreasing counter of steps to become a programmer. After four times, if I remember well, the Developer options will appear under System title. At this point, the Beginner's Guide instructions apply. In my experience i restarted more than once the IDE, but, anyway, everything works well, at the end.