Assuming that the mobile site URL is "m.ford-trucks.com", I have a a blue toolbar under the Ford Truck Enthusiasts banner that shows:
Home, New posts, UserCP, PMs all of which are selectable links.

When selecting UserCP, the next screen shows selectable links for:

Private Messages
Subscribed Threads

When selecting "Subscribed Threads" the only thing you can do in the mobile version is the select a subscribed thread to view, but you can not delete it like on the full site version.

If I select the "DEFAULT STYLE", (at the top right) next to LOGOUT, I can now delete any subscribed thread showing. All of this can be done on an Android device (my cell and Nexus 7 tested).

In "Default Style", it is better to view FTE with my phone turned horizontally to get the biggest screen view. My Nexus 7 screen is large enough to view vertically. Hope this helps.

Like BigF350 posted, you can change to the "Default Style" and you will see your full UserCP and change your preferences.