Apk files with adware or malware
Some uploaded files might show a warning (containing malware, adware, riskware or other mailicious content).
Files that are not 100% clean might not show up in recent files list or in search results.
When you click the detailed antivirus report of a file, you will see antivirus name (e.g Kaspersky, BitDefender, McAfee, Avast, etc) and the result next to it. If popular companies says the file is clean then most probably it is, even if less known antivirus shows a warning.
If your upload shows a warning you can click the link to request a rescan, and you ca also try to contact the antivirus company and send them your file, so they adjust their algorithms.
Antivirus companies periodically adjust their algorithms, we also re-scan them periodically.