1) . Amazon Music : -
Amazon music offers thousands of free music downloads. Once you have dowloaded a few mp3s from Amazon's free music download section, you can take them anywhere which means computer, iphone, android devices.
2) . Wynk music : -
Wynk music is offering millions of indian, pop as well as k-pop music. Not only bollywood songs but wynk also offers Indian regional language music like tamil, marathi, gujarati, punjabi and lot more. What you have to do is just to select the language and enjoy. Earlier wynk used to be a website but not its available in app form.
3) . Tunein.com : -
Tunein.com gives you access to more than 50, 000 songs. Actually it also offers other stuffs like sports and radio but considered best for music.
4) . Saregama.com : -
Through Saregama you can listen to millions of songs and download it.