For Android, there are OSMTracker or OsmAnd. Not sure there’s any for iPhone.

I haven’t done it yet, but OSMTracker lets you change the button layout so that you can simply click on one of its icons to add a specific type of POI.

Once back at the base, simply copy the GPX + JPG/3GP files onto your computer, and open the GPX in JOSM to see the track + pics/sound.