I don't know how many times I've been out shopping and wondered "wait, don't I have that?" before buying a book/poster/picture/DVD/collectible related to classic film. Thankfully, I came across a great app that I can use to curate my collections.
Snupps allows you to create boards for different categories, add pictures of your items, details such as price, author, year, and so much more.
And the best part is that I can manage everything from my desktop or pull it up on my iPhone when I'm out looking to add to my collection. The app is available on IOS and Android, and both versions work great!