I also like Navionics. Use if for tides and currents all the time. For $15 bucks, got all the charts for the entire west coast US along with tides and currents, about the same price as a single paper chart. Don't have to have a cell phone signal to use it either.
Are you using it with an iPad or iPhone? The Navionics app I'm using is
$7.99 and charts free.