I’ve just reviewed the status of this issue and made it public:
https://issuetracker.unity3d.com/product/unity/issues/guid/IN-70161
(same link expanded :
Unity Issue Tracker - Input stutters in Android player built with Unity 2021 and newer )
I’ve also added some notes as I think it could be related to this time.deltaTime change in unity 2020.2
The Android fix for deltaTime landed to 2021.1.0a2 for both OpenGL ES and Vulkan.
Time.deltaTime Not Constant: VSync CameraFollow and Jitter page-10#post-6630178
This newer task in the input backlog hasn’t been schedule yet.