my memory's a bit fuzzy, but for andriod/samsung you just download the .apk on the download listings, then you go to your file app, shoud be called "my files" in the samsung folder, and then tap the recent file (should be called garula.thefreakcircus-0.2.apk) or go to installation files and click it, hit allow download or whatever pops up, BUT BE CAREFUL FOR ANY SUSPISCIOUS STUFF, then it should download like a normal app.
idk about apple or any other brand since i only use samsung/andriod.
hope this helps! :)