Texting that you love someone more than pizza, comedic Internet memes, and word-play jokes that rely on double-meaning and homonyms are all examples of funny texts to send to family and friends. For example, a joke about a sandwich walking into a bar and being told that food isn't served there works well over text message because it is short and easy to understand.
Another innocent prank is when someone takes one family member's phone and sends a fake text as that person to another member of the family. It is best to choose these types of messages carefully, so nobody gets angry or ends up with hurt feelings. Instead of sending a fake message, another option is to use the auto-correct feature to program one commonly-used word so that it corrects into another word. For example, change "yes" into "snakes." This makes any text that person sends to another loved one really confusing and comical as they try to figure out what is happening.
Another joke is to act like the text box is a search engine, and someone sends a bunch of odd search queries to a loved one. This is funnier if the person sending the joke text is not known to be technically proficient, because then the recipient of the texts is more likely to believe that the messages are a mistake.
If someone is texting a significant other or a crush, alphabet jokes can be cute. For example, texting "I want to edit the alphabet to put U and I together" lets the other person know what the sender's feelings are in a cute, humorous and innocent way.