The KDL4R550C does not support Google Play, it is also not possible for the TV to download or add apps to it. Our advice would be getting a getting a media device to be connected to the TV (Bluray, streaming box, etc..) that supports the said app.
For further assistance, we recommend visiting our Sony Global Website for information on contacting the Sony Support Center in your region at http://www.sony.net/SonyInfo/Support/. Due to proximity, they are in a better position to provide support.
Best regards, -Mark
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