The HTC One M8 already received the official update from the manufacturer to Android 5.0 lollipop last January, the software update which introduced all the news of this new version of Android. According to the official Twitter of HTC UK, this device could have a new update on this year, specifically in August.
@JKMcCloskey Hey James, the HTC One M8 will have a Software Update for Android Version 5.1 and Sense 7 in August 2015 
— HTC UK (@HTC_UK) abril 29, 2015The new update for the HTC One M8 would be to Android 5.1 Lollipop, which would bring a new layer of customization Sense 7 that will also introduce improvements in this new update, settings as well as some new customization features such as themes and of course a better performance in their smartphones, fixing some problems of the previous version.
However, for the HTC One M7 the decision by the manufacturer is not known whether or not there will be also a new update, now what is confirmed is that for the HTC One M8 and will be deployed in August, anyway we are very attentive at any change.
HTC One M8 has a great LCD screen of 5 inches with a Full HD resolution of 1920 x 1080 pixels, it is a four cores Snapdragon 801 processor working at 2.3 GHz, which is supported by a RAM of 2 GB and a dual camera; being the main camera of 4.1 megapixel UltraPixel+2, which offers video recording in Full HD 1080p. Also worth noting that the internal memory depends on the variant selected by the user and can reach to 16 GB or 32 GB too.