The $10 monthly rate for music subscription services on mobile phones has become a standard, but now US service Rhapsody is trying a cheaper model. It’s offering the unlimited Rhapsody service to customers of US mobile operator MetroPCS for $5 a month – half its usual rate. Customers will be able to download as many songs as their handset-storage allows, although the costs of streaming those songs over the mobile network won’t be zero-rated. MetroPCS used to bundle Rhapsody into its more expensive data tariffs, so the new arrangement may put Rhapsody on the phones of a wider swathe of customers. Longstanding partnerships with mobile operators is one of Rhapsody’s trump cards as it faces competition from newer streaming/subscription services in the US: the $5 offer is a sign that pricing may also be one of its weapons for the battle. Rhapsody also notes in its announcement that 56% of all its listening came from mobile phones in 2012, up from 27% in 2011.