Look at devices such as the Huawei Mate 8, Samsung Galaxy S6/Edge+, Samsung Galaxy Note 5, Sony Xperia Z5 and Google Nexus 6P. Those are essentially the best high end phones you can buy. On the budget side of the spectrum, the OnePlus X, Xiaomi Mi series and Huawei P8 Lite are good choices for a reasonable amount of money. Head over to sites such as GSMArena to get all the information you need to decide which smartphone is best for you. My personal favorite is the Google Nexus 6P, as it runs stock Android and looks beautiful. Also take a look at Motorola's Moto X range.