#Android SDK GUI is here to stay
I am glad to inform the community that there is still a fully functional workaround to use the Android SDK whilst utilising the traditional GUI that most users are accustomed to. I am pleased to say that the GUI is here to stay (despite having been officially cut off sometime in SDK 26)
If you are starting from scratch I suggest you go through this post first: How do I download the Android SDK without downloading Android Studio?
Here the most important thing is that you must first install the base packages (i.e sdk tools, platform-tools, GUI sdk and AVD manager etc) found in the last installer version of SDK if you are starting form scratch, otherwise you can skip this step if you already a working sdk installation.
I discovered that even if you update the "SDK tools", the latest version that you can get is always 25.x.x
which has problem on its own as it doesn't allow you to run API levels 26, 27 or 28, as I pointed out in my post on another site: Can't start Android 8.0 Oreo on emulator: “Decryption unsuccessful”
After some weeks of investigation I figured out, this was something to do the outdated emulator which is no longer provided unless you running Android Studio (which is contrary to what we want to achieve)
From the looks of things it seems the emulator (originally distributed
as part of the Android SDK Tools) is no longer updated since version
25.2.3
Thus the workaround involves a "manual/forced upgrade" of emulator tools. Currently I successfully upgraded to version 27.3.8 (and running Android 9 smoothly).
The workaround
To shorten the story, firstly make sure the base packages are still intact, and upgrade the emulator as follows:
Instructions
- Download the latest (or suitable emulator) from the links supplied below
- When done, decompress the downloaded emulator.zip file and extract the emulator package to
%USERPROFILE%\Android\android-sdk\tools
or relevant path (yes you have to merge it into that folder, since the emulator doesn't have all libraries and files)
- After this your emulator will be updated (to 27.3.8 in my case):

Android SDK manager (GUI)
Now prepare your AVD (API level 27 or 28);
- Click on the AVD manager executable to bring the AVD setup dialog box.
- Choose the required parameters of the AVD and click ok to create.

Android AVD manager
Run the newly created virtual devices and you should be good to go:
- Select the virtual device and click start;



#Be sure to update the relevant tools, images etc to get the best experience
Important links
Base and Emulator tools(zip)
- Android SDK base installer (offline windows)
- Linux installer (can use wget also)
- Emulator version 27.3.8 (linux latest)
- Emulator version 27.3.8 (windows latest)
- Emulator 27.3.8 (mac os latest)
- Emulator version 26.1.4 (windows)
- Emulator version 26.1.4 (linux)
- Emulator version 27.1.10 (mac os)
Update: Added latest emulator versions
Update 2: Newer emulator versions
Special thanks to androiddev for providing links for linux, eaglemt and Vladyslav Panchenko for providing the links to repos and mostly important for mac os links.
Conclusion
It seems Google intentionally decide to pull the plug on GUI for standalone Android SDK in favour of Android studio perhaps because of potential security bugs, but whatever the reason,it may not sound convincing for someone just needing the standalone package...
Another way to explain all of this a bit simpler -->