Daz has 3D Content Database which appeared promising until major bugs began cropping up in th app.  I don't know if those issues have been resolved so you'll have to check their forum for further updates.  The alternative app, which is the core of 3D Content Database, is Brilliant Database:
http://www.brilliantdatabase.com/

You can create record entry templates with options to link records and attach external files.

I've encountered a database based on Microsoft's Access app.  Again, the versatility of this db is flexibility to modify and create record entry.  This one is a freebie but I can't recall where it can be found.