AT&T and Sprint turned to Twitter on Friday to announce record demand for activations and sales sparked by the launch of the iPhone 4S.

@Yungjohnnybravo @TatWZA

Sprint, which didn’t start carrying iPhones until this month, recorded its best day of sales in retail, web and telesales for a device family.

“We reached this milestone at approximately noon CT/1pm ET,” Sprint Product Chief Fared Adib said in an announcement. “The response to this device by current and new customers has surpassed our expectations and validates our customers’ desire for a truly unlimited data pricing plan.”

AT&T, on the other hand, touted activation figures and warned customers about potential activation problemsvia a tweet that said, “We are on track to double single day record for activations.This may produce slower activations for some: systems continue at record levels.”

Sprint’s tweet had an entirely different tone: “Thank you Sprint customers! iPhone 4S & iPhone 4 launch bring our best ever day of sales for a device family.”

Verizon Wireless spokeswoman Brenda Raney said the company is “pleased” with sales. “Nationwide our stores reported brisk sales and steady customer traffic all day,” she added. “We are looking forward to the weekend.”