iPhone app name: Item Minion for Diablo 3 (may release it for Android if it's helpful)
So, it does NOT give you an AH price (people keep thinking that it should, but as any player knows, that's not possible without farming extremely current AH data). But what it does do is give you the max stats an item can have (ie, a level 60 Chest Armor can have 269 Vit/200 Str with 3 core attribute affixes.) It also has stats for DPS/Armor and the rest of the stats (MF, Resists, Crit, etc).
Some ways, that you can use it:
You are leveling a new character and you need to know what the best stats on a helm is at level 36.
You got shoulders with 200 Str on it, how close to perfect is it? Max is 300... although max for DEX is 200.
Chest/Pants have the most VIT of 269, whereas Belt/Shoulders can have more STR than other slots...
You are getting as much crit as possible. What are slots contain crit, and what is the max (w/o having to guess on the AH until you hit the max value)
What is the prefix for the highest tier of resists on armor? (Chromatic)
Let me know what you think, and how I can improve it.
I understand that some of you may know this, but not everyone does, and I'm hoping to help those that want to know. So if you are too pro for this, then good for you. I'm sure there's still something here that you can learn from.
If there are errors, just let me know and I'll get it fixed. There are literally a few thousand data points, so it's hard for me to track down all the bugs. If you find bugs, please write them to this link: Item Minion - Diablo 3 Item max stats