Mobile Grid Client is an open-source messaging client and viewer for Second Life and OpenSim, the grid-based online role-playing game.

It is built on top of the open source library JMessage, and uses the open source library Zlib to allow for more compact messages. This allows the game server to receive messages and respond quickly, even on older, slower phones. It is built to be lightweight and use a small amount of memory, allowing it to run on any phone with a minimum of 4G.

In addition to being able to send text messages and images, it can also send and receive files, and it supports voice messages.