SnapShop Showroom
So, you've spotted your dream sofa that looks smashing in the showroom, but how will it look in your den? SnapShop Showroom overlays select products into your uploaded photo for the ultimate try-before-you-buy experience.
Cost: FREE

HomeSizer
Whether you're planning a sun room addition or are simply shopping for a new area rug, Home Sizer takes the guesswork out of your space's square footage. Simply upload your rooms' measurements and watch the app calculate its total area dimension. Bonus? Save your measurements by room to multi-task on your next trip to IKEA!  Cost: $2.99

ColorSnap
Looking for a shade of blue that perfectly reflects yesterday's afternoon sky? Upload any photo and watch Sherwin Williams color match a paint color (or entire palette!) perfectly inspired by the photograph. Genius.  Cost: FREE

HouzzInteriorDesignIdeas
With over 100,000 images and 250,000 idea
books in this eye candy app, you've got no excuse for an un-inspired room. Time to re-decorate!
Cost: FREE

Remodelista
Browse the homes of the pros, view stylish DIY ideas and gain tips for replicating the most beautiful rooms in the world -- all in one tiny, completely addictive app!
Cost: $2.99

LivingRoom for iPad - Floor Plans & Interior Design by Planet Next Living Room is an app designed from the ground up to help you do floor planning. As a carpenter you will often need to visualize how big something needs to be in a certain space. This app will help you visualize just how big your next desk should be. If you need to do any kind of floor planning this is the app to get. Cost  $4.99