VI. DISCUSSION AND CONCLUSION:
By reviewing the security aspects and existing threats for the two topmost smartphones OSs (Android vs. iOS), we try to explore strengths and weaknesses for both of them and try to make a fair comparison between them to have an idea that which one exceeds the other in temrs of different aspects of security technology. Android attained the leadership and won the two-race in the sales over iOS. This could be explained by aspects different than the security. Android is not limited to one specific smartphone, instead it is the OS for different devices and the first in the sales (Samsung devices) runs it comparable to iOS which run with Apple devices only. Looking for the security models of both the OS we could conclude that they use different security defenses policies beside some similar mechanisms. The iOS model is originally strict, layered, and multi-faceted security model. On the other hand, the Android model is heavily stands on the permission-based mechanism plus other mechanisms that are inherited from Android components such as Java language and its core OS i.e. Linux. iOS seems to be securer than Android but the latter tries to catch by the continuous updating. The threats fight is considered a real challenge for Android more than iOS. The high percentage of mal wares which target Android is too bigger than those hack iOS. This could be explained by the wide using of Android smartphones in the world and by the openness feature. A second reason, but makes advantage for Android, is the availability of solutions (anti-mal wares products and implement solutions in the literature) compared to poor efforts in iOS. Our comparison, based on different aspects and measures, shows the defense types, the strengths, and the weaknesses of both. Some of defenses mechanisms are applied in both and some are different for each other and this makes the security a power character in both. The vulnerabilities in Android are more than those in iOS and this is shown in the comparison. The strengths in iOS are more by a little than those in Android. Availability of solutions and anti-malwares products for Android is greater than iOS. The two ratings in the comparison are both won by iOS. The last but not least is that, Android is the forerunner in the race of business competition but the stockholders of Android's developments should do more efforts in terms of security to continue forerunning because iOS stills a strong competitive adversary and it gives a prime focus for implementing security technology.