It seems that Apple is working on a 64gb iPhone 4 model, Well according to the information provided by Unwire.hk prototype samples of the 64gb iPhone 4 are being sold in the Hong Kong’s “Grey Markets” over in China. According to the photos provided the phone indeed has 64gb of storage, The back of the phone states XXGB which is the same as iPhone prototype uncovered by Gizmodo last year. The back also states the model as 995-6049LL, FCC ID as BCG-XXXXXX, and the Model no. as XXXXX. Also the phone is not locked and in fully working condition.
We presume that Apple would be planning to launch the 64gb version of the iPhone 4 besides the iPhone 5 and iOS 5 which would easily solve all our memory problems.