At most schools, you're not going to be able to study "Android development" or "Java." You would likely have to study something like Computer Science and take an Android course if offered and a Java course within that Comp Sci major. Frankly, becoming a developer is not necessarily anything you have to go to school for in the US. You have a tech degree already, and you could come here and just do a bootcamp if you have the money. Also, if you're going to be a racial minority here and/or a woman, there are a couple of bootcamps that specifically want immigrants, racial minorities and/or women, i.e. c4q.nyc, Hackbright, etc, but c4q would be free if you get accepted. I have never had anyone tell me this, but I, personally, feel like the real problem with trying to be an Android developer is it limits job opportunities and you never know when the Android OS will become useless. As a developer, you want to know more technologies than just Android and Java.
I also think you should look more into which career you'd enjoy, not necessarily which is easiest to break into. Networking and developing are totally different, and you could choose something you don't have the capacity for or can't stand. To me, the easiest, quickest thing you could do is Web Development. Learn HTML, CSS, Javascript, JQuery, and even with just that knowledge you could land a job. You could learn HTML/CSS in just a couple of days, to be honest.