I have compiled an Android x86 system (KitKat 4.4.4), which can run live (from CD) or be installed on almost all laptops (and some Desktop computers). For example Acer (Aspire), HP, Samsung, Dell, Toshiba, Lenovo, Thinkpad, Fujitsu, Panasonic and Ausus laptops. The Android system is distributed in the form of an ISO file as the rest of my Linux distributions. I.e. you must (as usual) burn the ISO file to a CD if you want to run the system live on your computer or install it to hard drive. Read about how to burn ISO files.
Replacement for Windows, Mac or even Linux Desktop systems?
Some belive what I just said. The Android-x86 Project (Run Android on your PC) is about porting the Android Open Source Project to x86 platform. The Android-x86 Project’s latest release is Android-x86 4.4-r2 from 2015-01-01. The ISO file can be downloaded for free from SourceForge.net or Softpedia. My Android-x86 KitKat 4.4.4 build from 2015-03-01 will cost you 7 $.
Installing new apps
Google Play Store is pre-installed (among many other apps) so you can just go ahead and make your choices…
Install the system to hard drive
Say for example that you have a laptop with Windows 8.1 installed as the only operating system. If you just create one extra partition of about 5 GB you can install Android KitKat on this extra partition and then “dual-boot”. I.e. you can turn on your computer (called “booting it up”) and decide whether you want to start Windows or Android KitKat. Grub will be installed as boot handler/loader during the installation of Android KitKat. Note: The installation will take only about one minute.
What’s the point?
Well, if you like your Android phone and all the apps you have installed on it I’m sure you will also like to run apps from your laptop. Bigger screen and better sound etc.