Having burst from YouTube into the music world, the smart-mouthed singer That Poppy’s first EP shows off her winking sense of humor and wide-ranging pop savvy. “Lowlife” is a reggae-tinged toast raised from the gutter; “Money” takes aim at consumerism over deceptively glossy beats. The charging “Altar” pairs Poppy’s attempts to stop a wedding with propulsive dance pop, while “American Kids” sticks up for much-maligned millennials over a sumptuous beat. Confident and catchy, this debut is full of sardonic lyrics and pop promise.