The other is the choice of teachers and curriculum system of training institutions. When choosing an Android training institution, you should pay attention to whether there are excellent lecturers and whether you can give lectures to teachers.
The curriculum system is a relatively new mixed development of Android. If the curriculum system is not updated, don't choose older suggestions.
Some students can audition for two weeks, or arrange open classes on weekends. You can listen more and learn more before choosing. Besides, you need to work hard on your own. It is still easy to find a learning method to improve the efficiency of four months' study and improve your ability.