Here is also a nice topic with loads of feature wishes. I especially would love to see these things implemented in iOS11:
Here is my top 3:
08. Customisable control center
05. Multiple user accounts on iPad
31. Wi-Fi network priorities, like in macOS.
But it was really hard to pick out these three because I do want and hope to see all the below (16 + 3 of myself in iOS11. See the three I would like to see as well below:
* Finally build in a word sliding/swiping feature in Apple's own keyboard (so we won't have to use 3rd party ones like Swype, Gboard, Swiftkey) which tend to be buggy either by the API or by third parties
* Have a good search feature / a way to (de)select apps from the Slide Over/Split View supported apps list
* Kind of like 07. to make URL schemes mandatory for each app and preferabbly also actions within apps so you can easily launch those via other apps or e.g. widgets such as Launcher / Magic Launcher. Instead Apple recently started
asking developers to remove the URL schemes to Settings features
* a proper way of cache cleaning per app without deleting an app. Some apps do already have this features but others where I definitely want to see it like the horrible Facebook app don't have it.
As far as 90. I think indeed that Apple should finally implement that you can see a full day appointment in your calendar widget. I'm currently using a third party widget for that. Also I'm missing the support for Google's calendar way of address and showing
travel time (in minutes/hours) and distance. It now only works with an Apple calendar but I can't easily access that via iCloud to add appointments on a (Windows) laptop/desktop. I'm currently using a third party calendar instead (Week Calendar).
01. Ability to change default apps for Mail, Calendar, Contacts, ...
02. Widgets on lock screen, like Complications on watchOS.
03. Multi-tasking multiple instances of same app
04. Drag and drop between apps in split view on iPad
05. Multiple user accounts on iPad
06. Secure individual apps or documents with password or Touch ID
07. Some type of Finder or easier way of letting apps access each others files
08. Customisable control center
09. Force Touch in control center to select WiFi network, Bluetooth device, ...
10. Dark mode
31. Wi-Fi network priorities, like in macOS.
39. Weather on iPad
40. Calculator on iPad (too much to ask for a Graphing Calculator like Mac OS of old?)
82. Make it more usable for people who only use their local downloaded library, no Apple Music
86. Offline Maps
90. Just start paying some active attention to these Calendar/Reminder apps rather than keeping them so basic