They say that knowing is half the battle. If you were asked to make a list of all the CDs you own, would you be able to do it? Having a home inventory is not only helpful for insurance purposes, it's useful to maintain control over how much we own to avoid double purchases. The process of logging everything into a database also helps to reassess each and every item to sell or donate. Smartphones are perfect for the job, from reading barcodes to logging information. These 6 inventory apps are definitely ones you can count on.
iOS
Nest Egg is both satisfying to browse and easy to use. Enter product information by scanning the barcode, or take a picture and fill in the blanks. Intricate information like serial numbers and warranty can be recorded for quick access, with reminders for warranty expiration dates. Backing up and restoring your database is easy, and you can use AirPrint to make a physical copy. On sale now for $3 - $5 regular
Home Library
Home Library has your back for paperback, CD, DVD and gaming libraries. Information is logged by simply scanning the barcode — details like title, author, artist and such are filled in automatically. Where Home Library shines is keeping track of media lent out to friends and family. When the lending grace period carries on a little too long you can gently remind them in-app. $1
Android
This highly efficient app built for Android adjusts to your needs with custom fields and units to fill in whatever blanks that may arise. Scanning barcodes fills in item information and provides a picture to make building your inventory a snap. Databases can be imported/exported in .csv format and e-mailed for extra convenience. For the generous at heart who believe what's mine is yours, you can keep track of possessions that have been lent out. $5
Personal Closet
When it comes to itemizing your wardrobe, you need an app that makes browsing through clothes and accessories a snap. Personal Closet lets you take photos (from the camera or online) to create a visual inventory for your clothes. From this you can put together and prepare ensembles ahead of time on your handset or compare pieces while shopping. It's like travelling with your wardrobe wherever you go. $2
Windows Phone 7
Simple, clean and effective all come to mind when describing HomeCloud. Take photos of your possessions and organize them by category or room. There is also space for deep customization with category-specific details. Prices or serial numbers can be recorded for computers, TVs, appliances and such. The best feature is the SkyDrive backup for extra protection. $3
My Media Inventory
Entertainment is a huge part of our lives, so we feel it deserves an app of its own. My Media Inventory carries the same sentiments and keeps things easy without removing what's important. Scan the UPC of your books, movies or music, download the title and cover image, and repeat until everything is logged in. Simple is best. Free
Dirty Little Secrets of Tidy Families
Hillary & Michael's Refined Roost
Good Food to Share 
The Big Book of Small, Cool Spaces 
Apartment Therapy Presents 
The Eight-Step Home Cure 
Nomade Express Slee...
How To Cook Fluffy, Tasty Quinoa
My Staple Summer Cocktail Recipe: Campari & IPA Spritzer
iTunes Match = my CD inventory
Hmm. I use Delicious Library 2 for my books and dvds, but I don't know if it does the rest of the stuff in the house. I shall need to investigate, as I've been meaning to do this for insurance purposes.
Who has that kind of time?
Finn it does, and it's awesome!
Just a small note, Home Library is available on Android as well for a dollar (Pro Version)
Do any solutions offer OCR for things like vinyl records? Many older vinyl records were created before bar codes were in use. What would be the best way to catalog those?
We're doing a major inventory prior to a cross-country move (and as insurance backup since we're moving to an area with high risk for flooding if there are any hurricanes), and we found Personal Closet and Barcode eXpress both awesome apps for inventory purposes. Barcode comes with a 2-week free trial period, so you can try it out first -- we like it so much we bought it ($2). Personal Closet has a "lite" version but it saves everything to the phone -- you have to buy it to save to the SD card. Both are totally worth the investment, so far!
Cool sharing Jason, I like your app selection & Nest egg & personal closet I like most.. I definitely try it once, Currently I am using Ease My Wardrobe as a closet organizer & mix match my outfits. And To manage my home inventory I use Home Items Manager, it is just like nest egg but we can calculate total cost of Home assets with a single touch & at the time of natural disaster we can calculate total loss by removing assets from the list. Both are fully compatible with iPhone & iPad and it cost $0.99 each