A: That means the APK was built for a newer Android. Delete the file and download VidMate v4.1605 specifically for API 19.
Even with a smooth installation, older systems can behave unpredictably. Here are fixes for frequent problems: download vidmate apk for android 4.4 2
Because VidMate is not available on the Google Play Store, you must use trusted external sources: A: That means the APK was built for a newer Android