Checkout the Echo Dot details as below:
What is Echo dot?
With a new speaker and design, Echo Dot is a voice-controlled smart speaker with Alexa, designed for any room. Just ask for music, news, information, control compatible smart home devices and more. You can either use the crisp and clear built-in speaker or connect Echo Dot to your own other speakers using Bluetooth or 3.5mm audio cable
Meet the all-new Echo Dot: Our most popular voice-controlled speaker, with new fabric design, and improved speaker for richer and louder sound.
Voice control your music: Stream music from Amazon Prime Music, Saavn, and Gaana – just ask for a song, artist, or genre.
Bigger, Better Sound: Pair with a second Echo Dot for rich, stereo sound. Fill your home with music with compatible Echo devices across different rooms.
Ready to help: Ask Alexa to play music, answer questions, read the news, check the weather, set alarms, control compatible smart home devices, and more. Echo Dot is designed around your privacy. You can press the microphone off button to disconnect the microphones.
Connect with others: Call or message almost anyone who has an Echo device or the Alexa App, hands-free. Use Alexa to make Skype calls.
Use another speaker: Connect to you own speakers over Bluetooth or with a 3.5mm audio cable.
Alexa has skills: Alexa is always getting smarter and adding new features and skills like booking a cab, playing games, and more.
Voice control your smart home: Control lights, plugs and more with compatible connected devices.
You can buy on Amazon.
I think it is best in market :-)