Version 7.7 sees the complete conversion of the underlying database engine to SQLite. This now gives GSAK a much more robust and Industry standard database engine. For more information on other reasons for the switch see this link
Constant index rebuilds are now a thing of the past. Deleting of a single waypoint should now be near instant. Database corruption should now almost be non existent.
As expected the sqlite conversion of the "caches" table was huge, and there were many trials and tribulations along the way.
Backwards compatibility (generally for the Macro language and Grid) were especially challenging, but performance issues also came into play and many sections required a complete re write. For macro authors, be sure to also read the 7.7.0 Additional notes.
In general, the operation and display of the grid should be the same as previous versions. However, integrating SQLite with the grid involved a whole new paradigm, so you may find a few subtle differences here and there.
As on *overall* experience this version of GSAK should be quicker than the previous one. However, there are still a few areas that the old database engine did outperform SQLite. SQLite should be much more stable in general (especially after abnormal terminations, and power failures)
The main thrust of version 7.7 was always the conversion to SQLite, however there have also been a few new features added, including full cache attribute support.