Once you have a chart on your hard drive, how often do you update it? I'm running SeaClear II on my laptop, and tend to stick with the charts that came with the $20 bundle (I'm lazy). I've upgraded my local harbor chart at least once, but none of the others. Ideally, I should keep them all current, but that's not really practical. Update all covering areas within 200 nm every year? Service/software to do such? Perhaps an unfilled need? Perhaps there's a 'cloud' site that SeaClear II could go to for the latest charts rather than my hard drive?