Android is great if you are on a budget and can't purchase other operating systems for mobile devices. It is also great for installing third-party apps if you find one you like. Although there is a lot of customization options available, this may cause some users to become frustrated if they are unfamiliar with this system.
Kali Linux is especially well suited in environments where high security is needed for your custom developed applications. This is well suited for offensive testing your high security in house developed applications. It is also very good for doing penetration testing on in house developed applications and safe guarding them from external attackers. Kali Linux is tough for use as a day to day Linux operating system as this was never intended to be used by beginners and occasional Linux users.
It is very easy to use and the customer user interface is very smooth and logical. Rarely do applications crash and need reinstallation. The app store is secure enough to prevent malicious software from being advertised and potentially downloaded. Rebooting devices does not have to be a regular occurrence so this allows for high availability.
There have been only two times that I have needed to contact Android support for technical issues and both times I received some support. I received more helpful tips from Youtube, so I now bypass support and try to do most of our troubleshooting on my own with these support videos online.
Android allows users to customize their systems. It is very simple to use and there are a lot of devices running it. The interface has been improving a lot since Android Lollipop and it has been becoming more useful. For developers, Android gives more possibilities and the license for distributing your app is cheaper than the Apple Software Developer Program.