Hello,

I am Dnyanesh and am reaching out to understand a few specifics on Op TEE and custom TA development and deployment of the same.

The background is that we at Dygnify https://linktr.ee/dygnify were recently adjudged Winner https://www.rbi.org.in/Scripts/BS_PressReleaseDisplay.aspx?prid=56547 for Problem Statement 3: Exploring use cases/solutions for CBDC-R transactions, including transactions in offline mode, at Reserve bank of India(India's Central bank) second edition of its global hackathon - "HaRBInger 2023 - Innovation for Transformation” with the theme ‘Inclusive Digital Services’.

Our solution, a mobile application on encrypted SMS rails for CBDC-Retail transactions works without the internet. It is an inclusive, affordable and safe solution as it caters to both banked and unbanked users, works on smartphones and feature phones, remote as well as proximity payments and large as well as small-ticket transactions.

In order to build an additional layer of security for our proposed application, we want to process some critical part of our application as TA in the TEE of the phone. For this, we want to understand OpTEE as on 2023, as the documentation seems quite old.

In this context, may we request you to kindly let us know on: 1. How many processors currently as on 2023 supports the OpTEE? 2. What is the current market size of android phones with OpTEE? 3. Once developed done, how the deployment of TA can be achieved on different phones with android OS? 4. Can we get any support in TA development apart from available documentation from trusted firmware side?

Regards, Dnyanesh