Rounding out 2015’s top smartphones is another T-Mobile phone, the Samsung Galaxy S6 Edge. At $780.00, it is also the most expensive phone on the list. Like the G Flex 2, it features a curved glass design. At a full eight hours, the Edge has the longest-lasting battery in the group. One of its best features is an information stream, such as weather and recent emails, that a user can activate by swiping up and down the edge.