Why live wallpapers use phone call info When I install any live wallpaper, I am shown a list of items that the app will access. Most of these live wallpapers also access the phone call details. I cannot understand why? Is there any technical reason related to it or something else. Also I think it may cause privacy damage.

So should I allow these apps access my phone call details?
Thank you.
As you don't give any example, we need to guess. I doubt it's for "stopping themselves" for the call dialog like Amit suggests (as a background "live wallpaper", they don't need to do that specially for call dialogs: either they generally need it for any dialog, or not at all). I rather suspect some ad module behind this (see my answer here for details). For ad modules, the combination of INTERNET and READ_PHONE_STATE are quite usual: the former to retrieve the advertisement material, and the latter to access your IMEI for identification (good cop: to know which ads you've already seen so they are not repeated too often; bad cop: to get IMEI, IMSI, your phone number, phone numbers you've been in contact with -- so a profile can be built).

Note that the developer of the app (or live wallpaper in your case) has no control at all what those ad modules do. All he can do is to take care to chose a "good one", and avoid the "more malicious" ad modules.