Keeping Obsidian and Diarium in sync would be great!
My workflow is:
a) Capture all on Diarium
b) End of day, export Diarium entries for the day
c) Import into Obsidian
At the time of this writting, I have over 14k entries, starting from 1977.
I use Diarium On this day feature every day. Reviewing old entries, sometimes triggers me to change an old entry, improve the idea herein, complement it, etc.
However, these changes to old entries unsyncs the info previously exported to Obsidian since the Obsidian version does not have these changes done to these old entries.
If sync is technically challenging, maybe a temporary workaround could be to add an option to the export function to allow to select dates by MODIFIED DATE of entries. This way I could select to export entries modified today (or whatever range I define) and write those entries over the old unmodified entries on the Obsidian vault. For this to work, the file name of the original export and the new export would have to be exactly the same.
One other point related to export. The export function on the windows version of Diarium does not give the option of which data to export (tags, attachments, location, etc)! This forces me to perform the export on Android, then copy the file from android to PC. One extra step on workflow...every day...for the rest of my life! The windows version export function should have the same functionality as the Android version.