The Android Pay service at the moment has the biggest potential among Android solutions, as it can work on almost any smartphone with this OS equipped with the NFC module.
But, for example, in India this service is not represented. Google did not begin to promote Android Pay in this country because of the widespread payment system in India (UPI) (Universal Payments Interface). In particular, it is supported by WhatsApp and Truecaller.
As it became known, Google does not intend to break the current and prepares for India the Google Tez service. It will be a payment system with support for UMI, Paytm and MobiKwik.
Google Tez is also likely to be launched in Indonesia, the Philippines and some other Asian countries.