Low Price Calculator app for iPhone and iPad

"Lets shopping."
I went to Costco excitedly, but I faced a problem.
"Since the amount of products are different from ones which I always buy at the bottom prices, I can not know low or high."
This is an application for people like me.

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Features
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1) Calculate prices corresponding to the amount you see at the store, based on the bottom price you usually buy.
2) OK if unit is different. There is a unit conversion function.
3) Easy to register bottom prices.
4) Registered products are classified by categories.
5) Various units
Length：m, cm, mm, in, ft, yd
Weight：kg, g, mg, oz, lb
Amount：l, cl, ml, 升, 合, fl oz (US & UK), pt (US & UK), qt (US & UK), gi (US & UK), gal (US & UK)
Others：pair(s)  
            - (N/A) <---- no unit!

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Target OS : iOS 5.0 later
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