Hey folks,
Joining with my own list of things that attracted me to start using the Spotify app. First of all, I was a long time user of the classical walkman, then CD player and ultimately MP3 player before smartphones conquered the world. At the time I started using Spotify on my mobile I was listening to a lot of music on YouTube mainly for one reason - I was able to watch the videos as well. Spotify popped up as an option to replace the MP3 player in my pocket and it was already 2013. So here's my list:
1. As@Sebastymentioned, the free version is easy to start and use
2. Broad access to lots of albums and releases, there's always something unexplored
3. Convenient interface and simple design
4. Possibility to switch between online and offline mode
5. Great features to recommend you new music, artists and genres
6. The fact that content is being updated regularly and new stuff gets uploaded
7. Apart from my MP3 player, it also replaced some Internet radio stations
8. Nice library features - creating playlists, saving content and organizing it in folders
9. The podcasts
10. Listening habits stats
Probably I can name a few more, but these are the ones coming first to my mind.