What are /r/gamecollectors' favorite Products & Services?

From 3.5 billion Reddit comments

Sorry, it's called The Backloggery...it's been awhile since I was there. Backloggery Also...you may find /r/gamecollecting is more trafficked. I use both subreddits, but that one seems a lot busier.

It's not for managing your collection or keeping track of anything, but the unofficial VGPC app is great for checking prices on the go.

One thing you could do to manage your collection is just make a Google Drive spreadsheet. Document your collection from your PC and view the spreadsheet from the cloud on your phone. You could make a sheet for each console and set up columns with filters. I like this method because you don't have to rely on some app that might go poof.