Mycroft.AI - Mycroft is the world’s first open source assistant.
ifttt - IFTTT puts the internet to work for you. Create simple connections between the products you use every day.
Rhasspy - Rhasspy transforms voice commands into JSON events that can trigger actions in home automation software.
Google Assistant - Get things done with Google Assistant
Amazon Alexa - Virtual assistant developed by Amazon
Bixby - Advanced AI voice assistance for Samsung devices