I'm currently developing android apps and symfony based web sites.
In my personal project I faced performance problems while sending push-to-sync notifications to android devices through GCM.
Specifically, the VPS didn't fully process requests and run out of memory. The only way to solve was to hard reboot it.
I've successfully solved this issue by using the Http Cache. Because of a bad design, I firstly implemented the sync request as a POST call with all parameters contained in the body. This approach made impossibile to apply the cache mechanism due to not uniqueness of the url (different devices may have different status of sync).
To avoid an app update and its propagation time acro...