The Google Voice one makes sense to me. I don't have an Android phone, but the idea of having multiple texting apps that are slightly different seems amazingly confusing.

The horizontal support was the only one that didn't seem like a problem to me. Most Apple apps on iOS have horizontal support (Messages, Calendar, Camera, Photos, Mail, Stocks, Calculator, Notes, Safari, Reminders, Contacts).

But Springboard (the launcher) doesn't have horizontal support. That doesn't seem like a loss to me. If there was a second horizontal orientation, I've have to re-organize everything. You can't rotate every icon 90 degrees because there isn't enough space for the app titles in landscape.

A few other apps lack a landscape mode, but it doesn't seem like a big deal. Settings, App Store, Weather, and YouTube (outside of video playback) don't support it, but that doesn't seem like a big limitation.