For those who use Marine Navigator (Play Store version) and wish to add it to a new tablet / phone, there is a quite simple way to do this.. even though it's not in the Play Store anymore. And it won't cost you !
The following points need noting:
The advantage of this method is that you know exactly where the copy of Marine Navigator came from..(your own device), and you are not downloading something off the internet that "could" have been tampered with.
OK there's an article that deals with this:
How to transfer old Android apps into a new phone - The Verge
Gives an overview of the process
However, THIS is how we did it here, and we can recommend this method:
Now it's simply a matter of getting the new Marine Navigator APK from that folder and making backups of it somewhere safe. You could plug the device into Windows machine and copy it over. Or you could copy it to an external SD card
To install on the new target device, copy the APK over to it (via cable from Windows, or plug in the SD card you put it on), and tap at it. You will get warnings about installing from non PlayStore source. Allow.
It will be instaled, and you'll have your trusty Marine Navigator on your new tablet/phone. Make sure you have the SAME Google account on the new device as you had on the donor device, and that you are online. Open Marine Navigator.
Bingo ! all sorted.
Big thanks to Declan O'Sullivan for showing us this method.
The non PlayStore VMH version is coming soon for those who can't use this method.