Yes, Smartron SRT Phone does have the VoLTE support.
Yes, Smartron SRT Phone is a metal body phone. It is made of Aluminium Alloy.
Yes, Smartron SRT Phone does have the support for the Qualcomm Quickcharge and it does support fast charging.
No. Smartron SRT Phone does not have the MicroSD card slot. You will get 64GB internal memory and unlimited t-cloud space to store your data. Smartron SRT Phone also has OTG support.
Yes, Smartron has already announced that they are going to release Android Oreo update for SRT Phone customers in January 2018.