I was originally going to post this in your other thread, but it seems more appropriate here.
I can't add anything to the technical part of the discussion, but I'd say for a lot of people here, the 100 items is way too limited.
Does Snap have a similar limitation?
If you are still considering developing your own App (and want it to be useful to a large audience), make sure you allow significantly more than 100 items. 
With it including every possible thing (engines, rolling stock, accessories, etc), I'd suggest minimum 500, probably better over 1000, or best not limited.
-Dave
