Method to provide safety for customer of application's store

Rapid development of Android platform is followed by creating a large number of Android applications' stores. The biggest part of mobile viruses found in 2012 is oriented on Android-devices. As a rule, the User has to trust the check procedure of the applications in store, which shares this application. Any store may be an illegal intruder intentionally sharing applications and claim that they were scanned with antivirus. In such a way, promotion of some little-known stores becomes difficult. In the present work, the method for virus extension countering through the Android stores is represented. This method is based on the usage of proxy digital signatures and of $(n,t)$-threshold proxy digital signature scheme with Arbitrator. The $(n,t)$-threshold proxy digital signature with Arbitrator allows Developer of antivirus software carrying out the sharing mechanism of a proxy and right checking applications for the presence of malicious code between $n$ deputed Checking centres in such a manner that proxy signature can be calculated only in case of Arbitrator's participation and only if $t$ ($t<n$) Checking centres confirm the absence of viruses. The role of the Arbitrator may be laid on Certification authorities. If the User is sure of proxy signature accuracy for the file with application of the calculated $t$ from $n$ by Checking centres on behalf of the Developer, then he can feel certain that the application is safe and has been scanned with antivirus. Therefore, the User securely trusts the Developer of antivirus software and Certification authorities (Arbitrator) without fearing that some Checking centre will turn out to be an illegal intruder and sign insecure application. The suggested method of antivirus protection may be applied in stores for trust level increase among prospective customers.