The first set of samples for handheld navigation have been produced for testing. I have tested these with a phone (Nexus 5X) and with a 8" Samsung Galaxy Tab A tablet.
The collection for Volume 5 is located here
Here is the first of the maps in the collection.
Whilst the maps look good on a desktop it is different on the small screen of a handheld device. On the Galaxy Tab A (8") the text was a little small but still readable.
On the Nexus 5X phone the text was really too small to read easily and the top and bottom borders were masked out by the status bar and navigation bar for the phone.
It's not easy to cover all bases with the map templates. The intention with these diagrams has been to have them usable for a computer screen rather than a small handheld device. I will have a play to see if the text size can be bumped up a couple of points without having too much impact on the layout, so that the text is easier to read on a handheld device.
The navigational labels give a good indication of which way to swipe but the text needs to be more visible (darker) than the grey seen above. The arrows are OK but perhaps they should also be darker.
Overall I would think these diagrams will be straightforward to use for field navigation with a few tweaks and more testing will be undertaken in the coming weeks before spitting out a full set of PNGL diagrams.