• ping
• mic runtime permission request
• send only if has active client - add limit to store queue
• foreground notification
• synchronization
• client list ui
• multiple device test
• added talk button to foreground notification
• ConcurentHashMap

https://github.com/aahlenst/android-audiorecord-sample //android.os.Process.setThreadPriority( Process.THREAD_PRIORITY_URGENT_AUDIO );