I have used HTC desire 816 for about 3 years. It has got no issues till date. The phone has a 5.5 inch display and produces good brightness and colour reproduction. It is difficult to use with a single hand. Touch sensitivity is quite awesome. Rear camera is 13mp and produces good quality of image but suffers from shatter problem. Front facing camera is 5MP and has a great picture quality. The main drawback is its storage, it has 8Gb of ROM which is quite disappointing. It posses 1.5 gb of ram, though it has less ram but never lags and runs smoothly in normal as well as heavy usage. The speaker quality is awesome. One of the best features in this phone is its battery life, though it has 2600mah but it lasts more than a day in normal usage and lasts more than 6 hrs at heavy usage.
In 4G era this phone is not recommended as it is outdated and many better tech phone are available in market.