Possible fungal infection on austrailian green tree frog

[irThumper]

Do your best to get pics. Sometimes these guys can get a bit strange looking when their color changes, especially if it is cooler in their tank (like early morning or at night) when they can change color more slowly. Lime green polka dots or distinct blotches like Barbie mentioned, are something to suspect. Only way to know what you are dealing with, if your frog is not just transitioning normally, is to do a skin swab and send it off to a lab. You can have a vet do this or you can order a test kit (from Josh's frogs I believe) and send it off to RAL, a lab in Texas.

[Fergie14]

The spots have gone away

[irThumper]

He was probably just transitioning then.