I tried both AVD on Android studio and Genymotion emulator. My ubuntu 16.04.1 crashes (freezes) when the Android emulator starts. My computer has 16 GB of memory. This happens after I installed the latest updates for my ubuntu on September 19, 2016.
I had the same problem.
Choose "software" from the menu "Emulated performance", no automatic or hardvare
If this image is a "Play Store" (for example, pixel 2), this option is not available. If on the command line, use "emulator -gpu off"