DVSwitch Mobile is an Android PTT application for HAM radio operators to connect with other HAMs on the AllStarLink network.  The application uses Wi-Fi or Cellular data networks and has high quality voice and an intuitive user interface.  DVSwitch Mobile supports both smartphones and Network Radios with dedicated PTT buttons.

Configure your device to connect to a AllStar node by answering a few simple questions and you are ready to go.  Click on this link to get information on setting up IAX (Asterisk) contexts:
https://dvswitch.groups.io/g/Mobile/wiki/AllStarLink-setup-for-DVSwitch-Mobile

In addition to IAX2 support, DVSwitch Mobile now supports connections to USRP audio sources such as Analog_Bridge.  This is the bridge to many digital modes including DMR, D-STAR, Fusion, P25 and NXDN.

Key features
Network (Allstar/IAX2/USRP)
• Multiple IAX and USRP accounts are supported with login information and Caller ID 
• 16 digit keypad and macro support
• Maintains a list of connected nodes
• Popup when node connects or disconnects
• Popups for IAX2 text messages
• Field entry hints
PTT
• Dedicated PTT interface is available  (VOX operation is not needed)
• Hardware button for PTT on Network Radios supported (mappable and intent)
• Background operation supports PTT when screen is locked or the app is not in the foreground.
• Adjustable Push To Talk timeout timer with alerts
Audio
• Real-time high quality Digital Voice (VOIP) while maintaining low bandwidth usage
• Hands free and Bluetooth are supported
• In-Call and Music audio profiles
• Full duplex operation
• Adjustable transmit and receive audio gain per account
Misc
• Supports calling over Cellular (3G, 4G, LTE mobile data) and Wi-Fi
• Automatic reconnect on signal loss (optional)
• Status display for registration,connection state and amount of data transferred
• Lock screen displays registration and call status
• Supports portrait, landscape and small screen (Network Radio) layouts (lockable)
• Tone alerts for registration, connection and timeout (optional)
• USRP supports links to D-STAR, DMR, Fusion, NXDN and P25 networks through DVSwitch bridge


Note: Several features are still under development.

Android PTT client for AllStarLink IAX nodes (IAXRPT)