Sqlite update - best practise

When XOJO updates the Sqlite version - what is the best practice when dealing with legacy sqlite files? ie, I have a number of deployed web apps using sqlite. What happens if I recompile a legacy web app with later version? Will the app access the legacy sqlite file without corrupting it? What happens if, subsequently, a web app built with an older version of XOJO then attempts to read / write to that same sqlite file??

SQLite is a very reliable format. You would have to go back pretty far before you ran into any issues.

all the versions of SQLite v3.x should work with all other SQLite x3.x databases. Newer versions might have more features or bug fixes.

is sqlite supports multithread and mutliprocess in xojo?