Here's some feedback for the iOS App:
1. There's not a voicemail icon under the #1 on the dialer. Even though most people won't use it and will use Visual Voicemail instead, might be better to include it since the Windows app and other apps have it.
2. I mentioned this in another thread but want to emphasize it here. I would like to see full integration with Exchange Contacts in the iOS app where if one connects the Windows app to Exchange, those contacts automatically appear in the Cloud section of the iOS app. It'd be more reliable than trying to use the device section.
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