That restriction has been removed -- Microsoft says that you can ask Cortana questions, set reminders and basically do anything else you might usually ask the app direct from the lock screen. Microsoft has also made some updates to the default Cortana home screen, showing glanceable info like weather, upcoming calendar items, commute times and so forth. It sounds handy, but given that Android basically does this in the Google Search search app, it's also a bit redundant. For those that use Cortana a lot on their Windows computers and want easy access to that info on their phone, though, this updated app should do the trick. The latest version of Cortana for Android is available now in the Google Play Store.