how did it perform commercially?
It sold over nine million units in the first three days, setting a record for first weekend smartphone sales.
IPhone 5S
The iPhone 5S and 5C sold over nine million units in the first three days, setting a record for first weekend smartphone sales, with the 5S selling three times more units than the 5C. 
what is the latest ios version for iphone 5s iOS 12 what is iphone 5s? It is a smartphone that was designed and marketed by Apple Inc.
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IPhone 5S [SEP] Commercial reception
The iPhone 5S and 5C sold over nine million units in the first three days, setting a record for first weekend smartphone sales, with the 5S selling three times more units than the 5C. After the first day of release, 1% of all iPhones in the US were iPhone 5Ss, while 0.3% were iPhone 5Cs. Gene Munster of Piper Jaffray reported that the line at the Fifth Avenue Apple Store contained 1,417 people on release day, compared to 1,300 for the iPhone 4 in 2010, and 549 for the iPhone 3G in 2008 on their respective release days. This was the first time that Apple launched two models simultaneously.