TOPIC:

If your fishing any inland lakes, a topo map is a must. With the higher ended finders, at least from Lowrance (gave up on Humminbird long ago although their new stuff looks nice) you get maps included. They are not the most detailed but solid. But with this, you can use Insight Genesis. You can create your own maps and store them in the cloud and on your SD card in your finder.

However, if you dont pay for their service, they become public. This is terrible and awesome at the same time. I have found some lakes on Insight that I Ice fish on with extreme detail, better than navionics would ever give you, submitted by another user, that ultimately didnt pay for the service and they became public. Best kept secret! Download it to the SD card on the finder and boom!

If you have a Navionics card I highly recommend the app. They collect user gps and depth data to create highy detailed maps. It also works as a back up, even in the middle of the Lake with zero cell reception.