Navionics card renew subscription

[High Bidder]

I keep getting emails to renew my Navionics card that I purchased last year. Is this necessary? Any new upgrades listed wouldn't benefit me. Or will some features of the card or all of the card stop functioning  if I don't renew it?

[lost a lure]

Not Necessary. The card will still work. If there are updates for the card you wont get them. Depends on what body of water is updated.

[High Bidder]

Thanks, I wasn't sure if it was like my computer programs that I have to pay a renew fee every year so they keep working.