GroupSend allows you to send a message to many people in a few taps, if you want to send it to a contacts group a single tap is needed.
GroupSend integrates seamlessly with your favourite messaging software (Messages, iRealSms or biteSMS), no additional applications are installed.
Pressing the "add contact" button when composing a new message, it will now be possible to select more than one contact at the same time.
Also, in the groups listing, it is possible to select all the members of that group touching the group name.
See the screenshots to see GroupSend in action.
NOTE: it is recommended to define contact groups to get the maximum of the functionality.
You can use ABGrouper to do so.