One of reason is about Chip and Gyroscope probably, The Apple iPhone 4 will also feature an Apple-designed A4 CPU, following along the lines of the processor powering the iPad. The A4 processor improved power management, so the iPhone 4 will manage 40 percent more talk time on 3G networks (up to 7 hours), or up to 6 hours of 3G Web browsing or 10 hours of Wi-Fi browsing. The device can also play up to 10 hours of video, 40 hours of music, and should have an standby time of up to 300 hours.
The Apple iPhone 4 will also pack up to 32 GB of onboard flash storage, and will offer quad-band HSDPA/HSUPA for mobile broadband speeds up to 7.2Mbps downstream, 4.8Mbps upstream…assuming carrier networks support that technology. The iPhone 4 will also support 802.11n Wi-Fi, assisted GPS, Bluetooth, and packs and accelerometer, compass, proximity sensor, and an ambient light sensor,.