Let's say you're a competent Java developer and you'd like to build an Android app. I wish you the best of luck!
First you're going to need to pick an IDE. I've always used Eclipse and hey look, there's an Android SDK for Eclipse. Perfect! Download, extract, fire it up... Errors. This version of Android SDK requires Android API version foo, you have version (foo - 9), please use the SDK manager to upgrade. The hell, the IDE bundle doesn't even launch out of the box?
Alright, so you're distributing your IDE with an outdated version of your API, I can forgive that. Run SDK Manager like it suggested, let it do its thing,. Update available for SDK tools and SDK platform tools, looks good, do it! ...And, errors. Package not found, blah blah, let's see what Google has to say about this one.
OK, apparently hundreds of other developers are having the same problem and have, after much wrangling, figured out a solution on their own. I see, I have to go into SDK Manager Settings, create a new User-Defined Add-On Site pointing to https://dl-ssl.google.com/andr... because the URL that ships with the IDE is missing the "s" in "https" and that server doesn't have the right packages available to download. That highly intuitive process would surely have been my first try anyway, but at least someone else found the fix.
SDK Manager seems to find the packages now, great! Got past that hurdle so let's do the upgrade. Wait, now what! What do you mean you can't upgrade to SDK Tools rev. 23 while SDK Platform Tools 19.0.2 is installed? I checked the boxes to upgrade them both; if Platform Tools has to hit rev. 20 before SDK Tools can be upgraded, why is the installer going in the wrong order?
If and when you finally get the actual goddamned IDE installed and working, have fun with the official developer tutorials to create your first "Hello World" app. See, the API has changed over the years^Wmonth^Wpast week and so the app architecture that the tutorial talks about isn't valid anymore. XML files that it says should be there, aren't, so there's no way to follow along in the tutorial by editing them.
I gave up on Android and won't touch it again unless I'm being paid to.