Why can't I send group messages, pics, nor normal size videos to non-iphone users?
You must have cellular data turned on to send group messages or multimedia messages (MMS). That is the most common cause of what you describe. Even if you are on wifi, you must have cellular data turned on.
MMS will downgrade video, so video sent to non-iphone users will be made smaller and with lower resolution. iMessages to other Apple devices keep the resolution intact.
Do you have send as SMS turned on in your iMessage app?
