I don't know. I've got 8, but I am sure I haven't seen everything yet.
You've found:
a cool bug
a pretty leaf
a DVD of The Core (2003)
a secret glade
a holographic Charizard business card
a marsh wren
a tumbleweed
11 squares packed into a larger square
a DVD of The Core (2003)
a secret glade
a holographic Charizard business card
a marsh wren
a tumbleweed
a cool bug
a pretty leaf
11 squares packed into a larger square
a normal-looking leaf
an orb wren
a necklace of element samples whose symbols spell out your name
the Principality of Sealand
a rock with neat stripes
The Long Now Foundation's archive of every Animorphs book
a broken smoke machine
a friendly jumping spider
a spider-silk scarf
a block of scandium
a pair of platonic solids, not quite touching
a really cool data point
baby shoes (and baby)
a friend
two Andalites, one canonical
the Heart of the Ocean
a Rhode Island the size of an ant
a piece of pumice
I've been playing for a while. When I lag a lot, somehow it changes my phone background. It's happened twice now, probably the weirdest bug I've ever encountered.