Most modern Android devices allow storing large photos of each contact.
I tried exporting all my contacts, then importing them. All the large photos were lost.
How can you backup the large photos associated with each contact?
Backup and Restore
Following the app recommendations made in this XDA post How to backup local contacts with their high res pictures ?
I set a hi res
1984 × 1800 picture for contact and backed up using Super backup: SMS and contacts , took a backup , deleted the contact and restored
To my eyes, it appeared to be high resolution as originally set
The other app was not tried as it was pointed out in app review that it didn't work beyond 720 resolution
I tried to locate the storage of these high resolution pictures to manually verify the restored file size but couldn't. Method described in Where does android store contact photos ? didn't work
The reason I wanted to verify pre and post backup - restore process was to check if hi-res photos were backed up , not wanting to believe my eyes judging the resolution of the picture in a small circle on an LCD screen. So I asked this question High resolution contact pictures in Marshmallow - what is their size and where are they stored
As iBug explained in the accepted answer the resolution is capped to
720 by 720 irrespective of the picture size , an improvement implemented from KitKat days
It turns out that my suspicion was well founded !
96 by 96can be scaled up to
256 by 256by this Xposed module Clarity
Bottom Line: Any contact picture irrespective of original resolution will look no better than a
720 by 720 resolution, whether you use an app , Gmail sync or for that matter in any manner