The official blog for Android developers suggest to pay attention to the Russian market as the most promising to run your application.
According to a recent report conducted by OC&C Consulting and the Russian Association for electronic communications, the Russian market accounts for 45% of users under 35 years old. There are 233,6 million mobile subscribers out of a population of 146 million people. Owners of smartphones in Russia are among the interested consumers that actively use services of app stores and social networks.
84% of the smartphone market is Android device, and the average user in Russia spends 73.3 ruble per month for paid apps or services. Application developers have noted that Android users more active than iOS users. In mobile Commerce, advertising and mobile payments, iOS users tend to make larger, but rare deals, which cannot be said about Android users who are most likely to do a lot of shopping, shorter in length, but more frequently.
Google advises to pay more attention to the localization of applications. The translation quality should be on par with the original language. If possible, you should localize graphic elements and sounds in games. The company also advises to set prices lower than in Western markets.