According to this latest rumor from DigiTimes, Samsung may not be the only manufacturer in the market to try their hand at a 5-inch device. Samsung found great success with their "phablet-style" 5-inch phone, the Galaxy Note. It was such a success, (selling well over 5 Million units), that Samsung is set to release a sequel very soon. LG followed suit with their Optimus Vu and their upcoming Optimus Vu 2 5-inch devices. It looks like HTC is going to jump into the "phablet" game with their own 5-inch smartphone.
According to this latest intel, HTC plans to release their 5-inch phone with a whopping Full HD 1920×1080 resolution. If true, this will mark the first time we have seen such a tiny device with a full HD screen. Actually, the resolution of the display will only be 1794×1080, but this leaves exactly 126 vertical pixels for the Android navigation buttons. Supposedly, this device will be HTC's flagship for the upcoming Holiday season this at the end of the year, although it may actually launch as early as September or October. Not much else is known at this point, but we will keep you informed.
Source: UnWiredView and HTCOneForum