1.6.0.1
Normally when you are inside the map, the player is represented by an arrow. When you leave the map, the arrow transforms to a dot.
However when I do leave the map in MCPE version 1.2.9, the arrow isn't transformed into a dot. The arrow remains there, at the edge of the map.
The map goes up to Z+1536, so the arrow should transform into a dot past Z+1536, I go to Z+1800, and the arrow is still there. It's supposed to be a dot.
Thank you for your report!
However, this issue works as intended.
The change to a dot was removed in the 1.2.5 release. (Changelog)
If you would like to request that this change be reverted, you can do so on the feedback site.