Right after launching the series of Nokia X devices, Nokia mentioned it on their developer site that 75% of the app will run on Nokia X devices without any modification of changes. They have also provided an online way to check whether an app will run without any modification or not. While Nokia has replaced key APIs and services, including Google’s Maps and applications marketplace, with its own apps and Microsoft’s services, an XDA developers forum member has posted a way to root the Nokia X so that it could run the Google launcher, Play Store and other Google apps, including Gmail and Maps. In the picture it can been clearly seen that Google services has been integrated into Nokia X.
Though, Nokia is not going to make Google services included into their phones and the phones will use a third party market, Google services integration will help the users a lot, as most of the general users are not that much habituated to other download options other than Google Play.
The developer page for Nokia X is located here.