We like eBird (I’ve used it multiples this weekend) but the two sites are fairly different and there is no communication channel for discussing these kinds of issues.
Regarding sign and song annotations, here’s a draft I’ve made that I’m sure is incomplete, but I’ve tried to straddle keeping things basic and not providing an overwhelming amount of choices. I also tried to be pretty general and keep it to what I think are pretty commonly-observed signs. Let me know what you think, but please keep in mind these should not be super granular, and that new ones can always be added, I want to get a basic set up first. Also, these are in no particular order, and I left out organism, thinking this should be used only if the evidence is something other than the organism itself.
Type of Evidence
Scat (animalia)
Track or Mark (animalia)
Bone (vertebrata)
Feather (Aves)
Fur (Mammalia)
Shell (mollusca)
Nest (aves/insecta/mammalia/?)
Fruit (plantae)
Leaf (plantae)
Burrow (mammalia/reptilia/amphibia/insecta/arachnida)
Web (spiders/webspinners)
Molt (arthropoda/reptilia)
Call or Song (aves/insecta/reptilia/mammalia/amphibia)