New spec details have leaked for an unannounced HTC One M9 Plus, as well as a new HTC Desire A55 smartphone.

The HTC One M9 is among the most hotly-anticipated smartphones of 2015 and it's expected to launch with top-notch specs and features all around to make it worth the flagship title. In addition to the One M9, however, HTC is apparently also preparing a One M9 Plus variant codenamed Hima_Ultra, as well as a new Desire flagship leaked as the Desire A55.

The latest information comes from tipster Upleaks, who was behind most HTC-related leaks in recent months. This is not the first time news of an HTC Hima_Ultra device surface online, and Upleaks now claims to have more details regarding the handset's specifications.

According to an Upleaks post on Sunday, Feb. 1, the HTC One M9 Plus will have a 5.2-inch display with a QHD resolution of 2560 x 1440 pixels and come in two processor options. One variant will reportedly pack a Qualcomm Snapdragon 810 processor, while the other will feature a 1.5GHz quad-core MediaTek chip. The tipster also claims the One M9 Plus will come with a touch-based fingerprint sensor on the front. This would fall in line with a recent leak from @evleaks, showing the handset with a physical home button that could also serve as a fingerprint reader.

Upleaks further notes that the One M9 Plus will sport 3GB of DDR4 RAM, 32GB of internal storage capacity, a 20.7-megapixel + 2.1-megapixel Duo Camera system on its rear, and a 13-megapixel or UltraPixel front shooter. Other specs include a 2,840 mAh battery, BoomSound speakers, VoLTE and LTE Cat. 6 connectivity.

In addition to the purported HTC One M9 Plus, Upleaks also offered details regarding the specifications of an alleged HTC Desire A55. According to a new post on Monday, Feb. 2, the Desire A55 will boast a 5.5-inch QHD display (2560 x 1440 pixels), a 2GHz octa-core MediaTek MT6795 64-bit processor, 3GB of RAM, 32GB of internal storage capacity, a 20-megapixel rear camera, a 13-megapixel or an UltraPixel front shooter, and BoomSound speakers. This handset will reportedly have a battery of less than 3,000 mAh.

In terms of software, both the HTC One M9 Plus and the Desire A55 will allegedly run Android 5.0.2 Lollipop with HTC Sense 7.0 on top. The HTC Desire A55 could make its official debut by the end of February, while the One M9 Plus could arrive alongside the flagship One M9 on March 1, just before the Mobile World Congress (MWC) 2015.