OK - The UI is too stark. It needs color. The font is too much like WindowsPhone. The Music app needs album artwork. The 4 icons of the shortcut bar are ugly. The icons on the vertical row of the homescreen are too rounded and clash with the starkness and straight lines of the text font (choose one or the other, having both only clashes).

I hope the current theme is a placeholder and something better is used for launch.

When you pull down the "menu", you should be able to move the finger laterally to select the option if it's not an on/off toggle. Example:

Pull down until you see "Bluetooth: ON" - release the finger, it changes to "Bluetooth:OFF" and the menu rolls back up. Pull down until you see "Profile: Meeting" - moving finger left selects "Profile: Silent" and moving finger right selects "Profile: General" (releasing the finger selects the option and rolls the menu back up). Options that can be configured this way have two opposing arrows: "<| Profile: Meeting |>" or the various options side-by-side: "Profile: Silent Meeting General"

Also, only having two actions (swipe left and right) per "background widget" (plus touching the widget to call the app to the foreground) may be too limiting. I hope long-press calls up the close-button like on Harmattan and I hope that double-tap is supported too (for example, for "3D tiles", showing various information for the same app by "rotating" the tile). It's not as intuitive as swiping left-right for the 3D tiles as is beeing mooted for WindowsPhone, but Jolla is already using that for interacting with the widgets. If the widgets ("tiles") have only one face, only two actions are possible by swiping left-right. Multiply by four faces in "3D tiles" switching with double-tap, and you can have 8 actions.

And - YAY DOUBLE TAP TO WAKE UP!