These are the APK files that are published to the Play Store. That's the exact same files. They are digitally signed by a key from us, to ensure that the files are indeed from us. All the files we provide are harmless: the only collected data is crash reports (deleted after 3 months) and anonymous usage data (you can opt out) used both to improve user experience.
However, there's been a security breach in the Android code that verifies the digital signature of APK files. It means that APK files that are altered by malicious users can still pass the Android digital signature verification and can be authentified by Android as coming from us, which may not be the case.
Hence, to ensure that you are secure, always download your APKs from the Google Play Store or from this very website. Check also that the URL is mymine.upactivity.com.
All downloads made from the Google Play Store or from here are from us, meaning free of malware.
Downloads made from another location (typically from illegal download websites) may contain malware and still pass the Android digital signature check.