Is iPhone being remotely accessed? On a consistent basis, I try to close any open apps to save battery life. I close the apps by double clicking the home screen button &amp; then swipe the apps upward on the touchscreen to close. However, this is my concern.

Sometimes, when I check to see if any apps are open, to my surprise, a message can be open or a pic that I did not open. 

Is it likely my iPhone is being remotely accessed? It's locked at all times. I occasionally change the pass code as an extra security measure; installed the apps "Look Out" and "VPN Defender" but the issue is still happening. Not certain what is going on. Concerned someone is remotely accessing my apps/iPhone in the background; possibly by jail break software that is successfully able to do this using my phone number or apple phone ID.
Most likely what you are seeing is the cached image of the app. Your iPhone takes picture snapshots of apps as they run, specifically so that when you go into the app switcher, you see a graphic that looks like the app. It also refreshes this image from time to time. Most likely, you're just seeing a stale picture.

Also on an unrelated note, with the way iOS works, closing apps the way you are doing has virtually no impact on battery life. Placebo effect possibly, but not much more.