AndroidAuthority does their latest bang-up job in reviewing the Galaxy S4.  Starting with the physicalities, the S4 is both slightly smaller and lighter than its predecessor, the Galaxy S3...while having a larger screen...a full 5 inches with Full HD and 441ppi.  Useing Samsung's Super AMOLED technology really pops the screen colors and the high resolution ensures everything is sharp.  The Snapdragon 600 quad core processor powers the Galaxy S4 and in word...it's impressive, one of the fastest phones on the market.   The removable battery and MicroSD are again incredibly useful and the S4 includes a boatload of sensors...in fact more than any phone before including such stapes as gps, wifi, nfc, but adding a barometer, temperate gauge, rgb color sensor, infrared gesture sensor and compass.  It also includes an IR blaster to use the phone as a remote control and specialized software that utilizes the various sensors and make them useful truly make the software additions useful on the S4.  There's much more so watch the video and let us know your thoughts in the comments.