HTC (2498) is having a tough time keeping a lid on its upcoming HTC One flagship smartphone. UnwiredView’s Evleaks has just posted a full picture of the device, also known as the “M7”, which features a 4.7-inch display with a pixel density of 468 pixels per inch, a 1.7GHz quad-core Snapdragon processor and a 13 megapixel camera. UnwiredView confirms that the HTC One will launch on AT&T (T), Sprint (S) and T-Mobile on March 22nd and will also come to Verizon (VZ) at a later date, apparently to avoid cannibalizing the recently release HTC DROID DNA. The HTC One will reportedly sell for $199.99 with a two-year service agreement.