Always run the file through a service like VirusTotal before opening it to check for malicious code, trojans, or spyware.
To give you a more interesting and specific guide, could you tell me: did you download this file from (website/forum)? X_PLUS_00.apk
"Plus" apps often remove restrictions found in the official version, such as unlocking premium tools, unlimited currency in games, or removing ads. Always run the file through a service like