Along with the OP, I think I'm the only other Trainz iPad user in this thread. Trainz on the iPad is a technical marvel for the platform, and great fun for a bit of retro-trainzing, but not so good for serious route creating (although I'm sure that there are some really good routes out there somewhere). The iPad version makes it very easy for users to upload a route and session to the DLS, and I supsect that a lot of users are uploading routes a) simply because they can, and/or b) because they want to save a backup of something they're working on. The problem in my opinion is that iPad routes show as TS12 on the DLS, and can be downloaded and used in TS12. Whilst this is a nice idea, I think that the use of the main DLS for iPad routes is flawed. I would love to be able to round-trip a route between TS12 and the iPad but as far as I'm aware this isn't currently possible (maybe N3V have plans for this?) so downloading an iPad route into TS12 is likely to be at best an interesting step back in time to the early days of Trainz, and the limited content set available, and at worst a complete waste of time and bandwidth. I understand that iPad routes do have a tag in the config that identifies them as such, so I would have thought it would be possible to either add Trainz iPad as a search filter, to be included or excluded in dls searches depending on your preference.
I don't have a problem with anyone of any age uploading anything of any quality to the DLS,although I would like to see some discipline applied to screenshots so that they do actually show the asset in question. I tend to be fairly selective about my downloads and will usually only get routes from the dls that are either from creators I trust, or where I've seen plenty of screenshots or good comments. The bonus is that this often picks up some great dependencies that I would not otherwise have found, particularly when the object name is in a foreign language or follows some obscure naming system that means something only to the original creator.
R3