Navionics on Android - tidal data generated or downloaded?

[[3889]]

As per title - is there a need to go online periodically to get tidal data? If yes, how often?

 

[TSB240]

I have never noticed the need to be on line for using the local tidal info. I assume it uses a built in tidal algorithum.
The only feature for being on line is to dowload your choice of area map and for grib overlay.