Any of them should work. I have both a HTC PPC phone and an ipod touch and both sync to my Touchsmart without any problems.
One point to consider is, do you want a "smart phone" or a "Pocket PC (PPC) Phone"? The reason I ask is that smartphones do not have touchscreens while PPC phones do. My preference is for the PPC Phone.
David
http://i99.photobucket.com/albums/l299/xz550rj/HPMagicGiveaway.jpg
Woohoo! I won my Touchsmart!
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