Here is another kit for those of you serious about voice controlled apps. The AcuEdge ZLK38AVS Development Kit is designed for Amazon Alexa Voice Service development. It features the ZL38063 audio processor with a 300 MHz DSP.
The kit offers built-in support for 1 to 3 microphones linear or triangular arrays for 180-degree audio pick up. The ZL38063 audio processor that connects directly to a Raspberry Pi 3B.