Besides official Android SDK emulator which is damn slow and ugly, I have found Genymotion is quite good and awesome. In Windows platform Bluestack has done a very good job and their Android emulator is very fast and totally usable but sadly there is no Linux edition of Bluestack.
I found Genymotion could be a good replacement of Bluestack for Linux.
Installation of Genymotion is quite easy, you just need to download the bin file and then give execute permission to it and then run the file. Plus as you should have Virtualbox installed on your computer, it is a prerequisite. After executing the file, the setup program will take care of everything and install Genymotion properly for you. However, for downloading and using Genymotion you must register in their website and that is the only thing I really don’t like.
And still of course for development purpose my recommendation is official Android SDK emulator.
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