These are estimates so the data might not be all that accurate but interesting charts nonetheless. Overall they estimate that $61 billion was spent on digital games last year. PC was the biggest platform with $32 billion spent followed by mobile with $25 billion and finally consoles at last with $4 billion. The article down include more details and commentary.
https://www.dropbox.com/s/mcpf3a3y5yuhjk9/SuperData Top 10 2015.xlsx?dl=0