Are you referring to how Android will reclaim memory from inactive processes? Android handles memory differently than you expect, it tries to keep thinks in memory and only kills apps if it needs their memory back for a more demanding process.
Google consolidating most APIs into Play Services would ensure it's constantly active and never purged from memory, but the same isn't true of Gmail or other Google Apps. They can and are purged from memory as other apps demand more memory. That being said, I've encountered very few situations where any app gets purged from memory. About the only time this happens is if I play a game like Galaxy On Fire or decide to open 100 tabs in Chrome.
Yes I was, glad to hear GMail is subject to the same rules as other apps. Not sure what you mean by "Google consolidating most APIs into Play Services would ensure it's constantly active and never purged from memory"
> Not sure what you mean by "Google consolidating most APIs into Play Services would ensure it's constantly active and never purged from memory"
A lot of common APIs (Location API, Maps API, Play Games API, Push Notifications API, etc) have been consolidated under the Google Play Services umbrella process. Since these common APIs are used by lots of applications, this would ensure the Play Services process never gets booted from memory.
It also has the added benefit that applications using push notifications like Gmail don't need to maintain a background service because they can rely on Google Play Services to activate them as needed. Location based apps like Yelp can determine your location more quickly because Google Play Services is constantly monitoring it. All while reducing the over all memory foot print of applications because they're all deferring to Google Play Services.
Google can also change their APIs for services, upgrade to new protocols like SPDY, and developers don't need to update their applications because Google just needs to maintain the interface to Google Play Services. It's pretty clever.
If that's true then Google has given itself a good monopoly for email on its own OS, much like Microsoft did for Internet Explorer.