Not too sure about other systems, but on most browsers in Windows you should just be able to click on the download buttons. I don't have a phone compatible version at this time.
If you're still wondering about itch.io app compatibility, the downloads aren't labeled in itch. Compare it to Psychic Archeology Agency (your other game)
Those symbols help itch.io app download and install the right version internally. I can't download Summer Sweepers (or any other game) with the app without those symbols.