MIAMI (CBSMiami.com) - AT&T is celebrating the most successful launch of an iPhone model to date.

The mobile carrier says 200,000 iPhone 4S' were sold in the pre-order in just the first 12 hours, according to CNET.

"AT&T has seen extraordinary demand for iPhone 4S with more than 200,000 preorders in the first 12 hours alone, the most successful iPhone launch we've ever had," a company spokesperson said in a statement.

The sale started out rather bumpy though, with many customers complaining about the inability to process eligibility through AT&T and Apple online sites.

Apple, Verizon and Sprint have not released their sales figures.