Bringing simplicity to a 'smart home concept', technically the echo dot as such is a wifi device connected to the 'Alexa Cloud plastform', complemented with an embedded microphone and bluetooth speaker/receiver and an additional audio out jack connection at a very decent price.
Before going into detail in Alexa's possibilities and how to get it working outside of the official UK, US & German zone, let's talk about the device itself.
The internal speaker, despite its size, delivers a more than reasonable sound quality, more then enough for Alexa's voice feedback, and it will also suffice for small spaces.
For bigger spaces, the Echo Dot can connect to your sound bar or speaker system using a bluetooth connection or a wired connection using the audio out connector.
Nevertheless, a word of caution: when the audio jack is connected to an external speaker, the echo dot automatically switches off its internal speakers. This means that if your speaker system is switched off or playing another audio source, you will not here Alexa's voice feedback. Unfortunately, at this moment it is not possible to change anything about this. It is unclear whether there is a physical constraint or Amazon would be able to define a configuration parameter.
The Echo Dot does an amazing job at understanding your voice commands and questions, even from a distance and in rooms with more difficult accoustics and even slight echos.
The echo dot has an always on microphone detecting the 'wakeup word', which can be either "Amazon" ,"Echo", "Computer" or "Alexa". The good thing is that you don't need to pause to get the dot's attention but can immediately fire way your command or question.
Unfortunately, Alexa doesn't support combined commands yet. This means that you can ask Alexa what is the latest song of 'Pink', and you can ask Alexa to play a song, but cannot ask Alexa 'to play the latest song of Pink'. For the same reason you cannot tell Alexa 'to play your starred spotify playlist and switch your lights on' in a single command, you need to wake her up twice. Of course this probably is a matter of time to get this solved.