How to indicate that a list view can be swiped to reveal controls?

I would like some advice on any approach which is conventionally used for indicating that swiping sideways will reveal buttons.

I need to answer this design issue both for iOS and Android although the immediate context is an iOS app which is being enhanced after several years.

I am specifically asking in the context of list views, where swiping sideways will reveal two or more buttons, as seen in Apple's Mail in iOS7.

How to indicate specific sections of a page can be swiped addresses a broader question. The suggestions on that page are excellent but they would result in a lot of noise if repeated for many items on a list. They are also more appropriate when swiping part of a page results in a larger change in context.

Apple's HIG refers to the action in the section Users Know the Standard Gestures with the comment With one finger, to return to the previous screen, to reveal the hidden view in a split view (iPad only), or the Delete button in a table-view row but in my experience of talking to and observing users, they do not know the swipe to reveal buttons.

Update 2018-11-16 even after years of use, my wife still forgets the swipe to reveal buttons as a general list action although she has internalised it to delete things in a specific context of Outlook Mail on an iPad. Just an observation from a recent design review. I think it's important as the majority use of swipe as being delete is now a dominant learned behaviour, even when there are multiple buttons the default is if you continue swiping it activates the delete.

We don't want to have permanent markers as the list views already have a small down "vee" indicating they can be tapped to expand.

I have considered:

  1. A subtle animation on showing the list, with one or the items bouncing sideways a bit to show the buttons
  2. An onboarding variant of the above where this only happens during the first few launches of the app, or during an explicit walk-through of new features.
  3. Also triggering the swipe through a long-press, so people see the animated slide to the left if they press for some time on the list item.
  4. In one case, where a button used to be that is now one of the hidden buttons, react to a tap in that location so people reacting with muscle memory will see the button revealed as part of the set of buttons underneath.

Note:

There seems to be some hostility to this question, which I don't understand.

Someone else asked this question before and it was (incorrectly) closed as a duplicate.

Another question about a symbol for Swipe Left was closed as off-topic.

Update

Due largely to time concerns, no added affordances were built into the app. This may be updated for v2.1 after we see what features users have discovered, from Flurry logs.

The App store preview video includes a brief demo of one of the slide sideways features but that is only visible to people connecting to the store on a device. Apple don't (yet?) show previews to web browsers or in the desktop iTunes App Store pages.

If it was my preference, I'd go for both 2 (just have it animate a bit the first few times on those screens) and maybe 3, although long-presses on text areas also trigger label-based actions for copying.