Is usually pretty good for retail pricing. Tho some issues better than others. Using that in combination with the auction records can give you a good idea
Certification Lookup / Coin Inventory: The cert lookup features for both PCGS and NGC work great on a modern smartphone...they lock-on really quick. If you just register with your email for free (?), are the PCGS and NGC home pages able to hold your inventory of coins ? Makes it easier than copying it into notes and this way I have a written record of what I own when I go to coin shows. I noticed on the NGC App that after scanning a coin, it asks me if I want to add it (to inventory) but I wasn't registered.
I like coinoscope. Scan a coin and it tells you what you got. Great for foreign coins, but not foolproof.
Yes you can do set registries without the ability to submit. PCGS has a set registry app as well. And since you're on a tear bumping REALLY old treads the PCGS price guide/photograde was merged into one app since the initial replies.