If its your only option...
Then guess its worth the money. However, even though I regularly read books on my iPhone Kindle, and I read the New York Times from the newsstand, I find it difficult to navigate the magazine on my phone. By the time I make it big enough to read I lose the flow of where I am in the magazine.
However because the iPad screen is much larger I dont have this problem on the iPad. There it is an excellent way to check out the magazine.
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