A new sets of tests show the iPhone 7 Plus is more powerful than Samsung's Galaxy S8.
Chinese smartphone company Xiaomi launched its flagship smartphone on Wednesday.
Mehdi Hosseini, Susquehanna Financial Group, says consumers took a year to become comfortable with the curved edges of the Samsung Galaxy S6.
CNBC's technology product editor says you don't really need a new smartphone.
Hank Morris, Argentarius Group, says Samsung's new Galaxy S8 could help the company recover market share, while the rise in chip prices will drive earnings.
The Samsung Galaxy S8 and S8 plus are getting rave reviews for their displays.
Samsung shares got a boost after reports that Apple has put int a big order with the company.