I was playing while screen recording in a jungle trying to bring home an angry panda. I exited the game for whatever reason and, when I opened it again, I was extremely high in the night sky (Before exciting the first time, I was on the surface, maybe under some trees, but not up high). I was afraid, and so I exited again. Then, it teleported me all the way back to my world spawn. Unfortunately, that means it teleported me right next to a lava-filled ravine and a zombie. I had to make many copies of that world to save my stuff (thankfully, I had a bucket of water). To recap:

1. First, I was recording using the built-in screen recorder on the iPhone while playing Minecraft.
2. I exited the game (unsure of whether I stopped recording, but I think I can find out, if necessary).
3. I rejoined the game. I was suddenly very high in the sky (unsure of location, but I think I can find out, if necessary).
4. I exited the game again (unsure of whether I was recording at this point, but I think I can find out, if necessary).
5. I rejoined the game on a copy of the world (to know what to expect on the real one) and I was at my world spawn on the edge of a ravine. It was still night, and so a zombie came and pushed me in. There was lava, some obsidian, but no water. I practiced saving myself with a bucket of water several times. Sometimes, when I joined, I was already IN the lava. Eventually, I managed to save myself from that situation on the original save. The ravine is now filled with water and I managed to travel a few thousand blocks to get back home. I still need to travel a few more thousand to get to the jungle with my pandas, but everything is safe.