I just recently downloaded the Android SDK. Downloading all the packages in the SDK Manager will take way too much time. So I\'m wondering whether I should deselect all the plat
No, You don't need to download everything for every platform. You need to download only for those you are going to develop your application. E.g. If you are going to develop an application for Android 2.3.3 (API 10) then you only need to download for specific that platform only. You can choose to download support libraries from extra (If you need that).
EDIT
You also don't need to download all build tools. It's better if you use the latest one.
For more queries on build-tools you can look at this questions:
What are the Android SDK build-tools, platform-tools and tools? And which version should be used?
Not at all. You just need to install those platforms which you are targeting for your apps and which you intend to test your app with. If I were you, I'd install:
You should also install
Optional:
No, You don't need to install everything.
Install the "SDK Platform" for the Android versions you've set as minimum, target, and in-between the minimum & target.
Examples:
Target API 23, Minimum API 23
Target API 23, Minimum API 15
Extras
The Android SDK Extras are usually not required; but it is useful to be aware of them since they may be required depending on your use case.