What are some alternatives?
When comparing Heya and World Brush, you can also consider the following products
dropdrop - Leave messages where you travel for others to discover
Holo - Mix holograms into videos & photos in Augmented Reality
TapTag - Leave photos for other people to find
Figment AR - Turn your world into an augmented funhouse
Run an Empire - Turn runs into adventures
SPAYCE - Leave memories everywhere (iOS)