I spent most of the day looking at U Tube Videos about the Humminbird SI units and how they work and how to get the most out of them.
Go To UTube and search for "Humminbird"
I've had my 898 since last spring and am still learning new things about how it works.
BTW: I just got an email from Humminbird telling me about new software update features coming soon.
1. The ability to turn off the text screen on the left side of the SI view and only show the temp and depth in the bottom left corner of the screen. This give you full view of the left side of the SI screen's most recent data.
2. North up arrow on the display maps while in "track up" mode.
3. Casting circles displayed around the waypoints on the screen.
4 Will show the distance on the map view to each of the closest ten waypoints.
A few other changes are in the works as well as future waypoint managment software that's coming out this year hopefully.