The unlocked Sony Xperia Z1 with LTE connectivity, is available right now in Black. The Purple and White models are expected to ship on April 30th. The phone offers a 5 inch screen with a 1080 x 1920 resolution. A quad-core 2.2GHz Snapdragon 800 CPU is under the hood with 2GB of RAM on board and 16GB of native storage inside. The 64GB microSD slot in available for those who need more memory, and a 3000mAh battery keeps the lights on. Android 4.4.2 is now running the show. Keep in mind that this model is no longer the top cheese at Sony, replaced by the Sony Xperia Z2.
For those who plan on using this phone on T-Mobile's pipes, you're better off with the Xperia Z1s, sold exclusively by the carrier in the U.S. That version offers twice as much native storage (32GB vs 16 on the unlocked Xperia Z1), although the rest of the changes are cosmetic.
source: Sony via XperiaBlog