Lenovo S660 is an android powered smartphone which features 4.7-inch IPS Capacitive Touchscreen, 8GB Internal, GSM/WCDMA/HSPA+, WiFi/ Bluetooth, 8.0 MP + 0.3 MP Camera, Android 4.3 Jelly Bean, MTK 6582 Quad Core 1.3GHz. If you own this Lenovo S660, you may want to download the official Software and Utility which on the official download page is called as open source code. I am not sure what this file consist of because I am not an Android developer. Just in case you need it, you can download Lenovo S660 Open Source Code software from the link below.
You can also download user manual for Lenovo S660 on your language from here.