Huawei just announced Ascend P1 S, which is the company's latest flagship phone. This is currently the slimmest phone in the world with a width of 6.68 mm.
It comes with a powerful 4.3 inch Super Amoled screen with qHD (960 x 540 pixel) resolution. It might not be the best screen we have seen (typically on Samsung devices,) but is certainly in the top rung.
The 1.5 GHz dual core TI OMAP 4460 processor of Huawei Ascend P1 S is also the best in the business right now. There are other phones that use this processor, or processors with similar speeds. The device also comes with a healthy 1 GB RAM.