Lenovo has launched the ThinkPad S1 Yoga convertible Ultrabook along with a new range of ThinkPad Ultrabooks powered by Intel's fourth generation Haswell CPUs in India. The other three Ultrabooks are named ThinkPad T440, ThinkPad T440s, and ThinkPad X240s, which are all primarily for the enterprise segment. The new range claims to have better performance, reliability, durability, and battery backup.