In any case the Facebook, Twitter and Skype iOS apps are now equipped to deal with these handsets' larger screens.
The updates bring Facebook up to version 16 and Twitter up to version 6.15.1, and these apps' descriptions now note that they're "optimized" for iPhone 6 and iPhone 6 Plus.
Skype, too, now lists iPhone 6 optimization with version 5.6. Naturally these updates are available free in the App Store.
The Skype app's "what's new" section now notes a number of minor changes to how things are displayed, as well as improvements to "do not disturb" mode and the ability to mark conversations as "read" or "unread."
Skype Product Marketing Manager Lara Kingwell also wrote in a Skype blog post that the new app's iPhone 6-optimized resolutions display more recent chats and more messages in conversation view as well.
Are there any apps left that still look wonky on the new iPhones' screens? Hopefully they'll be addressed soon too.