Twitter sign-up spikes with iOS 5, valuation hits $8 billion

dick-costolo-TwitterWith its deep integration into iOS 5, Twitter has seen its daily-tweet rate and sign-up rate skyrocket since Apple’s newest mobile operating system launched last Wednesday, according to Twitter Chief Executive Dick Costolo, who spoke to a crowd yesterday at the Web 2.0 Summit in San Francisco.

“The iOS integration is going to be absolutely huge for us, even better than we thought it was,” said Costolo.

“I didn’t realize how frictionless this would be,” he said. “It’s so native.”

Twitter’s CEO said that the reason Apple and Twitter work together so well is that they both offer “simplicity in a world of complexity.”

As of last September, Twitter users were posting about 90 million tweets per day. That number has jumped 177 percent, to 250 million tweets daily.

In January of this year, Twitter had amassed 100 million users, 30 percent of whom were active, which means that number of users logs into the service, but doesn’t necessarily tweet anything.

Costolo said that, with the jump in active users, even more people will be able to find something that interests them through Twitter, and that sifting out the noise is one of the company’s biggest challenges.

“We’ve got to figure out how to capture the volume at the same time as separating the signal from the noise,” he said.

As the number of Twitter users rises, Costolo says that he believes it’s possible for the service to reach every person on the planet – but it’s not going to happen by adding a slew of fancy new features.

“We think that we can be on 2 billion devices around the world, and reach every person on the planet, and the way to do that is through simplifying.”

In addition to the reported traffic increase, Costolo also revealed that the company’s estimated worth is now up to about $8 billion, following the most recent round of funding.