Hope someone can help me here please, my head is spinning after trying to read most of the posts in this thread.

I've got a Samsung Galaxy S5 with Lollipop v5.02, screen resolution is 1920x1080 (not rooted)
I'm downloading one of the unlocked GB Discoverer Maps.

I would prefer to install everything onto the SD card if this is possible ?

Which APK do I need and do I need any other files / folder ?
I would be very grateful if you could give me direct links to everything I need please.

Can I also use any other Garmin maps while the GB Discoverer is installed ?
Is it also possible to use any of the Bluechart maps on it ?
Thanks in advance