I am looking to write an app that receives pushed alerts from a server. I found a couple of methods to do this.
Free and easy method:
If your target user base is not large(less than a 1000) and you want a free service to start with, then Airbop is the best and most convenient.
Airbop Website It uses Google Cloud Messaging service through its API and is provides a good performance. i have used it for two of my projects and it was easy implementing it.
Services like and Urbanship are excellent but provide an entire deployment stack and not just the push notifications thing.
If only push service is your target, Airbop will work fine.
I haven't used Pushwoosh, but is also a great choice. It allows push to 1,000,000 devices for free