The Register: Please, just stop downloading apps from unofficial stores: Android users hit with ‘unkillable malware’ . “Known as xHelper, the malware has been spreading mainly in Russia, Europe, and Southwest Asia on Android 6 and 7 devices (which while old and out of date, make up around 15 per cent of the current user base) for the past year from unofficial app stores. Once on a gizmo, it opens a backdoor, allowing miscreants to spy on owners, steal their data, and cause mischief.”