Ok, I know this HTC model is two year old. It was released in the year 2014. But I can vouch that this device still performs well and has been currently updated to Marshmallow. With several versions available based on different  geographic locations, thanks to devs who have really worked hard to make custom roms possible which further extends features.
As I bought this device within couple of months of it’s launch I have been following its development from the very beginning. XDA devs v_superuser, grarak has made milestone progress on this.
Since kitkat days several roms were available and I have tested them all. Few were partially stable, unstable and couple of them were daily driver as well.

Here I will try to provide a detailed over view on these roms. I own a dual sim India model (a5dwg).

CM 11 by v_superuser and grarak

This rom was the first available custom rom. Had its share of bugs which I will lost below. However I was smooth and snappy. Pure kitkat ui and root priciledges made this an instant grab.

Bugs: 

  1. Dual sim was not supported. Only SIM 1 used to work. To be precise the 3G sim used to work with incoming and outgoing calls. SIM 2 calling was not possible.
  2. GPS didnt work.
  3. Few application crashes randomly.
  4. External speaker clipping. 

Although its obsolete, download is not available through CM website, but you can grab a copy from xda. I will try to get a download link and will update later on.
Based on CM 11 several other flavours came into place.

  • Carbon Rom
  • PAC Rom
  • Mokee Rom
  • Ressurection Remix Rom

Most of them were meant for single sim models, hence were partially unstable with Indian dual sim phones.

CM 12 by grarak

Suddenly v_superuser went inactive from xda. Grarak took up the whole dev work and CM 12 was released and made official by him. New lollipop ui was interesting. Few bugs resolved but not 100% daily driver. Let me reiterate, I have tested these Roms in my dual sim devices. However the roms were made single sim compatible.

Bugs

  1. Dual sim not working. No sim 2 calling. Only sim 1 seems to work with data.
  2. External speaker clipping.
  3. GPS didnt lock.
  4. Random reboot.

Flavours based on CM12

  • Carbon Rom
  • Sense 7 by sun_dream
  • Insert Coin ( Only for single sim)
  • Ressurection Remix
  • Pac Rom
  • Mokee OS

Based on CM12 these different flavours had individual stability capacities. Such as Mokee OS and Sense 7 were most stable for dual sim models.
CM12.1

This was somewhat a break through. Several issues were fixed like GPS, Mobile data stability. But still dual sim was not fully functional.

  • Flyme OS
  • Mokee OS
  • Carbon and PAC rom

These were quite stable expect Flyme Os was a daily driver.

Download Links.

Android development for the HTC Desire 816

Original Android development for the HTC Desire 816

Mokee OS for HTC 816 very stable, a must try.

 

For any further help, contact me

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