​SpatiaLite is a relatively new GIS file format based on ​SQLite, which uses a single file to store multiple layers and data tables.

Exporting from PostGIS to SpatiaLite

Use ​ogr2ogr built with ​SpatiaLite options.

To create the SpatiaLite file export the first layer:

$ ogr2ogr -f SQLite -dsco SPATIALITE=yes myfile.sqlite PG:"dbname=mydb user=myuser password=mypass" myschema.mytable

And for additional layer/tables:

$ ogr2ogr -f SQLite -update myfile.sqlite b PG:"dbname=mydb user=myuser password=mypass" myschema.my2ndtable