A new version of the tracker is being tested on some users accounts. Here is a post made by reddit user: will650
“My tracker just updated with an enhanced “Nearby” feature.
Tested out this tracker for the last 20 minutes so here are my initial observations/impressions.
~ Each picture by the Pokemon is a PokeStop.
~ When you click the View button (picture 2), it pans out to picture 3. It then resets to the normal view of your character, but the PokeStop will still have the paw icon above it. Example
~ I have yet to see an icon that’s 1 or 2 paws, but the Pokemon don’t seem to be that far away from the designated PokeStop. I found the Pidgey within a block of that stop.
~ If the Pokemon despawns, you’ll get a notification that the Pokemon has fled and it will disappear from your nearby list and will be replaced by another Pokemon.
~ I’m assuming the ‘Sightings’ part of the tracker may be Pokemon that are within walking distance from you. The Spearow from picture 1 popped up right in front of me before I went to search for the Pidgey. So it appears the Nearby portion is only for Pokemon near PokeStops a bit farther from you.
~ I’ll play around with it a little more tonight. Will update if I notice anything else.
Edit: Looks like Pokemon right in front of you WILL show up on the Nearby tracker. This confirms that the icon will only display 3 paws. I didn’t notice this earlier, but the highlighted PokeStop will have it’s own radar ring around it. This probably means the Pokemon you’re tracking will be within the radar ring. Also, I snapped the picture at a bad time – the PokeStop ring is just as big as your character ring. Knowing that, now I’m assuming that the ‘Sightings’ part of the tracker is for Pokemon not near a PokeStop.
Edit2: Based on some testing of when the Nearby Pokemon disappear and reappear, it looks like the max distance for this tracker is roughly 500 meters.”