The "out-of-office" reply is a commonly used automatic email reply that lets people know you will be away from your email for an amount of time, so they won't think you are ignoring them. Just about every email client has this tool, including one of the most popular - Gmail. Apple Mail and other email managers sometimes don't let you set up out-of-office responses. For Apple Mail you'd have to do it in a roundabout way, setting up rules on your desktop Mail app. It's a better idea to set it up at the source.
Judging from the number and magnitude of incidents involving Facebook over the past few years, that the social media giant is playing fast and loose with user data is probably an understatement. While it is now putting extra effort into user privacy, it has a long way to go, and you should do everything in your power to protect your data. One of the easiest paths for your private information to leak out is through third-party apps that have permissions to your account.
There are many apps that will manage your email accounts besides the iOS Mail app - Thunderbird, Outlook and Gmail will all do the job, to name a few. Outlook is popular with a lot of businesses, so if your work email is managed by Outlook you might want to add your other emails just to be able to access them all in one place. Or maybe you prefer the Outlook interface to that of Mail.
Many websites and third-party apps will ask for permission to access your Google account for a variety of reasons. They will request different levels of access, ranging from basic profile info used to "sign in with Google" (similar to sign in with Facebook) up to full access to view and edit all data and even create content, which is a scary prospect. It should be obvious by now that you need to take great care regarding your data privacy, so you should know how to see who you've given access to, and how to revoke it if need be. Here's how to do it from your iPhone or iPad:
Apple has replaced iPhoto with the new Photos app and launched the iCloud Photo Library feature. Now, if you want, every photo you take with your iPhone or iPad will automatically upload to the iCloud Photo Library. You can even use the library to save the full resolution images while leaving smaller, optimized images on your iOS device to save space.