When sliding from the right apps not showing up

[Greysquirrel]

When I swipe from the right to see other apps the only app that shows up is mail, when I first got my iPad a week ago when I swipe from the right it showed a vertical row of apps. Looked in settings and could not see anything that looked like a reference to this operation, but then being new I may not know what to look for.
Also sometime when I trash all messages and they go to trash the next time I open mail I have a message saying messages could not be trashed, then I trash them all again and they stay trashed, then a few days later I get the same message. Not a big problem but is there a fix for this?

 

[J. A.]

To your first question:
There should be a small line visible on top of the bar with the Mail app in Slide Over view. Slide it down, to show the other apps as well:

 

[J. A.]

For your email account:
Go to Settings - Mail, Contacts, Calendars on your iPad. Tap the account that doesn't always remove emails. Tap the email address at the top, then slide down to Advanced and tap this as well.
On the next screen, take a look at Mailbox Behaviours. Select "Deleted Mailbox" there (not the one in "Move discarded messages to"):

Tap it, and make sure that the account is removing "On the server", and that something like "Deleted Messages" is selected:

Hope that helps.

 

[Greysquirrel]

Thanks everyone for your replies, can't remember how many times I swiped my finger on the mail to see if it would move as that seemed like the logical thing to do, but never ever did I notice the black line at the top. Thanks for the explanation of that and thanks for the email suggestions from those who replied to that question.

 

[J. A.]

You're welcome.