My Auntie has the BB Curve and i find its easy to use but i just brought the BB 9700 bold and its quite easy to get along with... little hard to conect bluetooth but i can giude u through it...
Easy answer. The Bold has the 3G and the newer trackpad. If you google around there are several sites which compare. The 9700 is clearly the better phone which is also going to be compatible to get the new OS of 6.0 due out this summer.
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