Sprint (NYSE: S) customers continue to flock to rivals like AT&T (NYSE: T), which has added more customers thanks to its exclusive relationship with Apple’s iPhone. That helped widen Sprint’s Q3 loss to $478 million from last year’s $384 million. Revenues fell as well, dropping more than 8 percent, as the recession also put downward pressure on its business. In all, Sprint lost a total of 135,000 net retail subscribers in the quarter. The Overland Park, Kansas-based carrier has tried to strike deals with other device makers and software providers, like the Palm Pre and Google’s Android, but so far, those efforts have come up short.

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Citing the economy and greater competition, Sprint said that post-paid churn in the quarter was 2.17 percent compared to 2.15 percent. Things were a little better when it came to prepaid churn, though, which was 6.65 percent in Q3, versus last year’s 8.16 percent.

Looking ahead, the company says post-paid and total subscriber full-year losses should improve this year, but it didn’t offer any specifics.

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