I've been testing my app on mobiles and want to include channel API so I could get live notifications( as it is included in desktop version ) but I noticed that I don't get anything from the channel on my phone.
I've been looking for the solution but the only thing I found is C2DM - https://developers.google.com/android/c2dm/
but it's no longer under development.
I've been also testing google channel API with Ripple Mission Control on Chrome, and when it's turned on I only get note that I connected to channel but when I make some changes in my app I don't get anything. When I turn it off then everything works..
Note that the channel API is not supported for Java client (or iOS):
https://code.google.com/p/googleappengine/issues/detail?id=4189
Yes, you should use each platform's native push notification technology - the successor to C2DM is Google Cloud Messaging:
http://developer.android.com/google/gcm/index.html
On iOS I believe it is APNS:
http://en.wikipedia.org/wiki/Apple_Push_Notification_Service