A few developers have already rooted the Samsung Galaxy S4 before its official April launch. Early adopters can check out the video below for all the necessary information one will need to gain root access to the unreleased device. The root is only for the Exynos 5 Octa model, not devices sporting Qualcomm's Snapdragon 600. According to rumors, this eliminates 70% of the initial Galaxy S4 batch shipping in a few weeks. The "octa" units are being reserved for European countries with poor LTE availability.
Both AT&T and regional carrier US Cellular announced they will start accepting Galaxy S4 pre-orders on April 16th. T-Mobile will offer the GS4 contract free, but locked, starting sometime in May. The flagship handset from Samsung will cost $250 with a two year contract. It is unknown how much the unsubsidized T-Mobile model will cost.