T-Mobile: First day for Apple’s iPhone was ‘gangbusters’

Photo: BTIG’s Walter Piecyk

FORTUNE — No one knows how long it will last, but the pent-up demand at America’s fourth largest carrier was palpable Friday morning as lines formed outside T-Mobile USA stores for the first time in memory.

The lines weren’t overwhelming, and they dissipated before the afternoon, but it says something about the draw of Apple’s (AAPL) iPhone that customers will still queue up to buy the newest one nearly eight months after it launched.

The reason, of course, is that it had a captive crowd: 34 million T-Mobile customers locked into contracts with the only major U.S. carrier that, until Friday, didn’t have a contract with Apple.

T-Mobile made the most of the opportunity:

  • Undercutting (slightly) the competition by selling the iPhone 5 for $99.99 down and $20/month for two years ($580 total)
  • Offering trade-ins (until Father’s Day) for old iPhones that could bring the upfront cost to $0.00
  • Running ads for its “un-leash” unlocked-iPhone scheme on TV, radio and YouTube (see below)
  • Launching (a few weeks ago) high-speed LTE networks in seven metropolitan areas

“Today has been gangbusters for T-Mobile,” said T-Mobile’s Mike Sievert to anyone who asked. “We experienced lines out the door this morning at nearly all of our almost 3,000 stores nationwide.”

Below: T-Mobile’s TV ad, to what sounds like a Jimmy Hendrix soundtrack.

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