The Sinch SDK allows developers to add voice calling and/or instant messaging to mobile apps. It handles features like signaling and audio management while and also allows for the creation of a user interface.
Pusher has announced an enhanced "Sandbox" plan to its tiered pricing program. The original Sandbox version permitted 20 concurrent connections, and 100,000 messages per day. Now, the plan allows 100 concurrent connections and 200,000 messages per day. The move is aimed to attract new developers.