Say you got hooked on a streaming service like Spotify, but you’re hitting something of a wall — 20 million songs is just too overwhelming and intimidating. Your playlists are stale. “The thrill is gone!” you wail. Cue Bluesify — a Spotify app to browse and discover more than 100 blues artists in 28 subgenres, from pre-war and ’30s Delta to Tom Waits and the White Stripes. Bluesify is the first in X5 Music Group’s 2013 series, and the Stockholm company is hoping to replicate the success of Classify, its Spotify app with 100,000 monthly users, making it the 14th-most installed app on the massive music subscription service. X5 is the No. 2 digital classical label in the United States, and the company says it has used Classify to boost classical track plays by as much as 3,400% on Spotify. Bluesify will aim to do the same for X5’s blues partners Verve Music Group, Sun, Blue Note, Alligator and Vanguard. Bluesify runs inside the Spotify app and takes just seconds to find and launch. The app is all about playlists, and there’s at least 1,000 of them — from Halloween-themed lists featuring “Mojo Hand” by Lightnin’ Hopkins to Alligator’s own custom playlists of Johnny Winter or Albert Collins. Along the top of the screen are basic navigation suggestions like Home, American Blues, World Blues, Genres and Artists, of which the lattermost is easily the most powerful. Blues icons are arranged chronologically with cool illustrations, so listeners can drill down on Robert Johnson, Ledbelly, Nina Simone and Jimi Hendrix. This blues browser is so helpful, Spotify should come bundled with tuition at music academies. First, however, it must come to the iPhone.