Text messages are not going through

Please open your Settings app, choose Messages section and set your settings as suggested below:

For iOS 8 devices the suggested settings are:

iMessage - ON.
'Send as SMS' - ON.
MMS - ON
Group Messaging - OFF
Subject Field - OFF

For iOS 7 Users the suggested settings are:
iMessage - OFF.
'Send as SMS' - ON.
MMS - ON
Group Messaging - OFF
Subject Field - OFF

If you are trying to send pictures please note that your cellular carrier might have limitation to the number of recipients in group text. We suggest you to ask your carrier if they have such limitation. Usually this limitation is up to 10 recipients when you send message with image.