Have you ever wanted to share your iPhone or iPad with someone else? If you share your Mac with someone, you can each have your own account. OS X is designed for multiple users. But iOS is not.
iOS does give you restrictions, the ability to limit the type of content accessible from your device. Restrictions lets you limit access to specific apps, like Safari, FaceTime, Camera, the iTunes/iBooks store, Siri, and AirDrop. You can prevent people from installing and deleting apps, from changing privacy setting, and a lot more.
Though restrictions is powerful and needed, it does take time to set up and, once set up, there is no easy way to switch everything back to all access mode for your own personal use.
iOS also offers guided access, an accessibility feature that lets you limit a device to a single app, control which features are available. Guided access is extremely useful if you will be setting up a kiosk or distributing devices to a controlled group, such as a museum tour, or students in a classroom.
There are no doubt technical hurdles to overcome to make iOS a truly multi-user OS on the order of OS X. And some might argue that the iPhone and iPad are personal devices, not designed to be shared. But how many times has someone asked to borrow your phone to look something up or, as a parent, how many times have you wanted to give your phone/iPad to your child, perhaps for entertainment on a long car ride.
As an aside, the latest version of Android, Lollipop, ships with multi-user support built in. I can’t help but imagine that engineers at Apple are working on solving this problem for iOS, as well.
In the meantime, how about this idea? Add in support for a single profile tied in to restrictions. Then tie that profile into Touch ID and Passcode.
The idea would be, let me set up my restrictions profile with all the limitations and privacy I’d like, then tie that to a unique passcode. If I login with my regular passcode or my fingerprint, I get full access. If I login with my guest passcode or fingerprint, I get the restricted access version, ideal if I want to hand my phone or iPad off to someone. No worries about accessing private information or accidentally deleting something of value.