I have a number of mobile devices including iPhones, an iPad, and Kindle Fires. All of them can connect to my wifi network fine, and get Internet connectivity. After being idle for a variable amount of time (sometimes very short e.g. less than a minute) they lose Internet connectivity. When this happens, they maintain the wifi connection itself.
This problem does not happen on my laptops which include multiple Mac laptops and one Windows laptop.
I've tried a number of different things to resolve including upgrading OS versions and tweaking wifi router settings e.g. IP assignment TTL, signal type (B/G/N) and security mode, but no dice.
Any ideas why this happens and what I can do to fix it?
UPDATE: My AppleTV was also connected to the same wifi network, yet my iPhones couldn't see it to do AirPlay. Once I rebooted my router AirPlay was available again. AppleTV doesn't require a live Internet connection to do AirPlay, just requires a local wifi network. Because of this, I suspect the wifi router is dropping the network connectivity to the devices, or vice versa. It's not conclusive, but this seems to rule out the AT&T modem or router (which my wifi router connects to) being the problem.