Those APK can be sketchy at times. However they usually work. You can tell right away if they are fake because they will either not allow you to download or will download a generic APK like the site @Teoman linked which actually downloads an app called "AIO Downloader" however you can see this when it asks for permission before installing. I looked everywhere for this app and it doesn't seem to be available anywhere. The other couple of sites that had it have dead links and all of the developer pages and website are 404. So I would say you're out of luck.
