iPhone 6 and iPhone 6 Plus shipments in the second quarter of 2015 are expected to exceed 60 million units, more than the originally expected 50 million units, according to Taiwan-based supply chain makers.

As the sales performance for the iPhone 6 series has been better than originally estimated, Apple may defer the launch of new iPhone models, the sources guessed.

Currently, SiP (system in package) ICs used in iPhone series are packaged by a few companies, including Advanced Semiconductor Engineering, ShunSin Technology Holdings and Lingsen Precision Industries, but the number of suppliers is likely to be decreased to only two in the future, the sources indicated.

In contrast to the iPhone, China-based smartphone vendors were originally expected to have increased shipments in the second quarter but shipments for them have not increased, implying that smartphone demand in the China market has not yet rebounded in the second quarter, the sources said.