Well, Apple was perhaps a bad example since they tend to hold their value for a little longer than most brands, but iPhones weren't the same price for years. I really don't know where you got that from. An iPhone 4 is far cheaper now than it was on release 3 years ago.
I live in Greece I don't know the exact amount but basically every new version of the iPhone had the same price (say 620 € for 16GB). However, inflation is measured against CPI (consumer price index) not a single product which might have specific market niche (i.e. Luxury goods).
Now, a currency that doesn't slightly inflated tends to be seen as an investment by consumers rather than an exchange medium. I would very much welcome bitcoins as a payment since I believe their value will go up in the future, but how many people are willing to end bit coins instead of dollars?
Deflation is relative. One thing is deflationary relative to another. Dollars are deflationary relative to iPhones. Dollars are inflationary relative to Oil. People will buy oil because if they wait to buy it tomorrow their dollars will buy them less. People won't buy iPhones because if they wait to buy it tomorrow their dollars will buy them more.
If that were true, no-one would have bought an iPhone and Apple would be penniless (USD etc are deflationary relative to technology items).