Tinode - Tinode Instant Messaging
Invoca - Call tracking & analytics software
WhatsApp - WhatsApp Messenger: More than 1 billion people in over 180 countries use WhatsApp to stay in touch with friends and family, anytime and anywhere.
CallTrackingMetrics - Know who is calling and how they found you. Maximize the return on your advertising.
Signal - Fast, simple & secure messaging. Privacy that fits in your pocket.
Marchex - Marchex is a mobile advertising analytics company that connects online behavior to real-world, offline actions.