if you are going to software updation please note one feature to be added ,which one is that conatct picture size when get a call it should be full size.Now its showing circle shaped.I really doesnot like that one.
iPhone 5s, iOS 7.0.6
OK, sorry, sorry, sorry, my previous post was somehow inaccurate. Here's what really works on the iPhone 6 (at least), to get the caller's picture at full screen size. The height of the picture must be at least 960 pixels, and the width at least 640 pixels. The picture can be resized in Contacts with the slider without consequences on the full screen display, but be aware that if you move it within the frame the actual size can change and thus reduce a dimension below the required threshold.
What is still exact from my previous post though, is that to get a large picture when tapping the contact's image on the iPhone, the width of the picture must be at least 282 pixels.
To get the contact picture to fill the entire screen when someone is calling, rather than just a small thumbnail, add the picture using Contacts on the Mac. If its width is at least 282 pixels, it will display full screen. The height can be anything, even one pixel. To test if it works without receiving a call, open the contact on the phone and tap its picture. If the picture opens in a larger form, then it will fill the screen when a call is received.
This was tested on an iPhone 6, I cannot vouch for the required size on other models.
Tell Apple:
http://www.apple.com/feedback/iphone.html
contact picture size
