Free chartplotter & maps for iPad?

[XtaSea]

I want to have a backup to Navionics. What is the best free app these days?

Used OpenCPN on the Android and Windows laptop, but it doesn't work on iPad.

[skipperearly]

qtVlm could be an option for you and once you like it consider to contribute

[XtaSea]

skipperearly, have you used it? Care to share your experience?

[skipperearly]

I use qtVlm for some years now, primarily for weather route planning, which I find much more intuitive and functional than the wr-pi in opencpn.

Had just a few questions and got instant and helpful support. Only snag is that I cannot use the Navionics charts in native (vector) form. Workaround with mbtiles is cumbersome.